Philosophical transactions, Vol. L. Part I. For the year 1757. / Giving some account of the present undertakings, studies, and labours, of the ingenious, in many considerable parts of the world.

by Various; Royal Society

II.

Chiron and Achilles. The latter of these is standing, and has a plectrum in his right hand: the former seems to embrace his noble pupil with his left arm, and with his right hand to strike the lyre, as teaching him to play upon that instrument. But the most remarkable circumstance in the figure of Chiron is his reposing his hinder parts on his left haunch upon the ground. Yet this attitude, as well as the other particulars mentioned above, is expressed in an antique gem, of which I have seen a copy at Rome.

I shall conclude this paper with an account of the statues, which stand in several rooms adjoining to the unfinished part of the palace, and were found (as to the far greater number) at or near Herculaneum.

In the First Room.

An equestrian marble statue of M. Nonius Balbus the elder, which is intended to be placed in a large entrance on the east side of the palace, to answer to that of his son, which is already set up on the other side, facing the bay of Naples.

In the Second.

Nero and Germanicus, considerably larger than the life, but squeezed somewhat flat by the weight of the lava, or other ruins, with which they were once overwhelmed.

A man in a sacrificing habit.

Two others in the toga, and two women in the palla.

All these are of bronze.

Statues of marble deposited here are the following, viz.

At the entrance, a matron larger than nature, with strong expression in her face.

Two colossal trunks in a sitting posture.

Three statues of one of the Agrippina's.

A Roman matron, or empress, with remains of red painting on the extremities of her palla.

Three other matrons.

In the Third Room.

Bacchus. A muse. A fragment of a statue in the pallium. A fine statua togata with the head veiled, larger than the life.

Another very remarkable figure, whose face resembles in beauty that commonly attributed to Venus, tho' the dress and other insignia plainly indicate a Pallas: for her head is covered with an helmet, below which her hair falls down long and dishevelled. Her left arm is enveloped with her ægis, which is large and expanded, so as to form a kind of mantle. Her garments are thin, and fit close to her body in strait plaits. She is in a posture of running, or striding, with her feet at a considerable distance from each other, and her arms extended different ways; an attitude strongly marking the utmost eagerness and haste.

Next appears a Vertumnus. A fine figure of a philosopher. Volumnia and Veturius. A lady with a thin stola. A Venus. A boy of exquisite workmanship. A small statua togata.

In another part is a Faun of bronze, reclined, with his right hand lifted up, and his leg extended. This figure (as we were informed) was found accompanied with seven others of the same metal, which now stand in another chamber, viz. two young men in a running a posture; four females somewhat resembling vestals in their habit, excepting that all their heads were uncovered, and those of two of them were adorned with vittæ, or filets. Lastly, a young man of a small size, cloathed, with his arms somewhat extended.

There remains but one more figure to be taken notice of in this collection, viz. that of Serapis, with Cerberus at his right hand. Ancient writers[48] enable us to account for this appearance, by informing us, that Serapis (besides his other characters of Æsculapius, Sol, Osiris, and Jupiter) was accounted the same as Dis Pater, or Pluto. Upon this hypothesis none can doubt of the propriety of Cerberus's attending upon this deity in the figure before us, as well as in three others given us by Montfaucon[49].

If we desire to enter into the mystical reason of this representation, we may learn it from Porphyry, viz. that Serapis[50], being the same as Pluto, had dominion over the evil dæmons; and that those beings were figured by a dog with three heads; meaning the dæmon subsisting in the three elements of water, earth, and air.

Give me leave to add further, that I find, by my journal, that upon viewing this figure, I took notice of a dissimilitude in the heads of it: but as it did not then occur to me, that they were ever expressed in any other form than the canine, I did not examine minutely into the difference: but, upon recollection, I am now inclined to think, that that monster might have the heads of three several animals in this piece, as he has in another, given us by [51]Montfaucon: which mode of exhibiting him was (according to that learned [52]antiquary) invented by the Egyptians; a circumstance not to be wondered at in a people, whose imagination teemed so plentifully with monstrous ideas of all kinds, as theirs is known to have done.

To the same original we may refer the serpent twisting round Cerberus in this monument; as we see two of the same species encircling his heads and body in that mentioned above[53]. As I know no particular relation, that the serpent bears to Serapis, considered as Pluto, I can regard it here only as a sacred symbol in the theology of the ancient Egyptians; and, as such, properly attributed to an attendant of one of their chief divinities.

I shall trouble you but with one more observation upon this article, viz. that (if I may trust my memory for a particular omitted in my notes) this is the statue, which being the principal one found in an ancient magnificent building discovered about seven years ago at [54]Pozzuoli (in conjunction with other circumstances) occasioned it to be called The Temple of Serapis. As this place seemed greatly to merit the attention of the curious in antiquity, we procured a plan of it, drawn by a native, who has free access to it and (if I thought it would be acceptable to that learned Society, of which I have the honour to be a member) the said plan should wait upon them, accompanied with some observations upon it by,

SIR,
Your most obedient,
humble Servant
John Nixon.

London. Feb. 24. 1757.

P.S. A long room is designed to be fitted up in the King's palace at Portici, for the reception of all the antiquities found at Herculaneum, &c. This apartment will be lighted by thirteen windows on the side towards the Cortile, and adorned with forty columns, partly of verde antique, partly of alabaster with brownish veins, and other beautiful marbles, found in divers parts of the King's dominions. Between every two of these columns will be placed a group, statue, or bust. The compartments in the walls will contain the ancient paintings. The other curiosities are to be deposited in cases made for that purpose; and the pavement will consist intirely of the finest pieces of Mosaic work, that have been found in Herculaneum, or any places within the Neapolitan state.

XIV. An Account of the Effects of a Storm of Thunder and Lightning, in the Parishes of Looe and Lanreath, in the County of Cornwall, on the 27th Day of June, 1756. Communicated to the Rev. Jeremiah Milles, D.D. F.R.S. in two Letters, one from the Rev. Mr. Dyer, Minister of Looe, and the other from the Rev. Mr. Milles, Vicar of Duloe, in Cornwall.

Read Feb. 24, 1757.

ON Sunday the 27th of June last it grew on a sudden as dark as a winter evening: soon after, the lightning began to flash, and the thunder to roar. The claps were near, and extremely loud; and the lightning was more like darting flames of fire, than flames of enkindled vapour. Happily no damage was done to the town of Looe, which lies very low; but at Bucklawren, a village situated on the top of a hill, about two miles from hence, a farm-house was shattered in a most surprising manner. The house fronts the south. The windows of the hall and parlour, and of the chambers over them, which are in the front of the house, are sashed. The dairy window is the only one on the west side of the house. The chimnies are on the north side; and at the south-west corner there is a row of old elms on a line with the front, the nearest of which is ten feet distant from the house. The lightning seems to have had a direction from the south-west to the north-east. It first struck the bevilled roof of the south-west corner, near the eaves of the house; made a large breach, and tore up the floor of the garret, near the place where it entered, and descended by the west wall, in oblique lines, into the chamber over the parlour; but not having sufficient vent that way, it darted in a line from S.W. to N.E. against the north wall of the garret, where meeting with resistance, it broke down the floor near the north wall many feet wide, and carrying the ceiling of the parlour-chamber before it, ran down by the wall of that room in direct lines. Where it descended on the west and north walls it made large and deep furrows in the plaister, and even tore out the stones and mortar. A large splinter was struck off from the bed-post contiguous to the north wall, and the bed was set on fire. The chimney-piece was broken into many parts; the window-frame was moved out of the wall, every pane of glass was broken, the under sash was torn in pieces, and a large piece of the chimney-board was thrown out of the window against an opposite garden wall, about 20 feet from the house. As the lightning shot thro' the window, it found a small cavity between the wall and the slating with which the wall is covered, where it burst off the slates as far as it continued in a direct line downward, and threw them at a great distance from the house. Notwithstanding this dreadful havock, the force of the lightning was not spent; the window gave it not a sufficient discharge. From the chamber over the parlour, it descended by the north wall to the room under it, which is wainscotted, tore off the cornice the whole breadth of the room, and some mouldings from the wainscot; broke the glasses and Delft ware in the beauffet; shivered the shelves of a bottle-room; and, ripping off a small stock-lock from the door, burst it open, and made its way chiefly thro' the window, the frame of which was moved from the wall, and the glass shattered to pieces. Near the bottle-room there was a hole struck in the partition-wainscotting, which divides the parlour from the hall, about eight inches long and an inch broad: through this crevice the lightning entered the hall, which serves at present for a kitchen, and meeting with some pewter in its way, it flung it from the shelf about the room; threw down a large iron bar, that stood in a corner and which seemed to have a trembling and desultory motion; carried the tongs into the chimney, and threw a tea-kettle, that stood there, into the middle of the floor; moved a large brass pot out of its place, which was under a table; and then darted thro' the windows, carrying away a pane of glass intire out of the upper sash to the distance of many feet. The mistress of the house and her son were sitting at this window. They were the only persons in the house, and providentially received no hurt. Some part of the lightning found a way between the door and door-case of the hall. The door is pannelled: and the lightning, in passing thro', penetrated into a close mortise, and split off a large splinter from the outside of the door, close to the tenon. In its course it left a smoaky tinge on the wall and timber, like that of fired gunpowder. A sulphureous smell remained in the house many hours. Another (or probably a part of the same) flash of lightning struck the dairy window, melted the lead, and burnt the glass where it penetrated, and set the window-frame on fire. From thence it darted in a line from S.W. to N.E. downward, made a large hole in a plaistered partition near the floor into the barn, shattered a large paving rag-stone in pieces, and tearing up the ground, I suppose, sunk into the earth. The elms were affected with the lightning, particularly that nearest the house, from the top of which to the root appeared large furrows in the moss, which grew on the bark, in some places in an irregular spiral, but for the most part in a perpendicular line; and from the root of it the ground was torn up in furrows, as if done with a plough-share, about six feet long, the furrows gradually lessening according to their distance from the tree. All this was done instantaneously. How amazingly swift, subtle, and powerful is the force of lightning! I am,

Reverend Sir,
Your most obedient Servant,
James Dyer.

A Letter from the Rev. Mr. Milles on the same Subject.

ABOUT four of the clock on Sunday afternoon, the same day that the lightning struck the farm-house at Bucklawren, it fell upon another house called Pelyne, in the parish of Lanreath, about six miles distant. The house fronts the east. The chimney, which is at the north end, is cracked, and opened about two or three inches wide, from the top to the roof, where it entered the slating thro' a small hole on the eastern side; forced its way thro' the upper chamber, where it melted an old copper skillet, a pair of sheepshears, and some odd brass buckles and candlesticks that lay on the wall; consumed the laths adjoining, and then made its way thro' a small crevice in the upper part of the window. Another and more severe part of the same lightning descended the chimney; struck two women down who were sitting on each side of it, without any further hurt; overturned a long table, that was placed before the window in the ground room, upon two men, who were sitting on the inside, with their backs towards the window. One of these men was miserably burnt in his right arm. The lightning seems to have struck him a little above the elbow, making a small orifice about the bigness of a pea; the burn from thence to the shoulder is near an inch deep. His right thigh was likewise burnt on the inside, and the outside of his right leg, from a little below the knee, quite over the ancle to his toes. Both knees were burnt across slightly, and his left thigh. His shirt-sleeve, and the upper part of his waistcoat, were reduced to tinder: the buckles in his shoes were melted in different parts, and in different directions. He has not been able to use his arm since; and is under the care of a surgeon, who has reduced the wound to a hand's breadth, which was in the beginning advancing fast towards a mortification. The other man was but slightly wounded. The lightning afterwards found its way thro' the window in three different places; melted the glass, leaving a smutty tinge, like that of fired gunpowder. A boy, about ten years old, son to the under-tenant, was also struck down, as he was standing at the door, but not hurt. The father and his daughter felt no ill effects; but saw the lightning roll on the floor, and thought the room was on fire.

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XV. An Account of the Peat-pit near Newbury in Berkshire; in an Extract of a Letter from John Collet, M.D. to the Right Reverend Richard Lord Bishop of Ossory, F.R.S.

Newbury, Decemb. 2, 1756.

My Lord,

Read Feb. 24, 1757.

NOW I am mentioning the peat, I beg leave to assure your Lordship, that tho' some persons have asserted, that after the peat has been cut out, it grows again after some years; yet this is not true of the peat found here, none of the peat-pits, which were formerly dug out, and have lately been opened again, affording the least reason to justify such an opinion; but, on the contrary, the marks of the long spade (with which they cut out the peat) are still plainly visible all along the sides of the pits, quite down to the bottom; and are now as fresh as if made but yesterday, tho' cut above fifty years ago: which shews also, that our peat is of too firm a texture to be pressed together, and to give way, so as to fill again the empty pits: which perhaps may be the case in some of the mosses, where the pits are found after some years to be filled up again.

The town of Newbury lies north and south, in the shape of a Y, cross a valley; which valley runs east and west, and is here about a mile broad, the river Kennet running along the middle of it. The peat is found in the middle of this valley, on each side of the river, extending in all from between a quarter of a mile to about half a mile in breadth and in length, along the valley, about nine miles westward, and about seven eastward; and I believe much further tho' not yet discovered, and perhaps with some intermissions.

The ground it is found in is meadow land; and consists chiefly of a whitish kind of earth: under this lies what they call clob, being a peat-earth, compounded of clay, of a small quantity of earth, and some true peat: it is from four to eighteen inches thick; and where the earth above it is but thin, it is sometimes full of the roots of plants, that grow on the surface of the ground: and if the meadow also be moorish, the sedge and flags will shoot their roots quite thro' it into the true peat, which lies directly under this clob.

The top of the true peat is found at various depths, from one foot to eight feet below the surface of the ground; and the depth or thickness of this peat is also very different, from one foot to eight or nine feet, the ground below it being very uneven, and generally a gravel. My friend Mr. Osgood has dug two feet into this gravel, to see if any peat lay below it, but could not find any.

The truest and best peat has very little (if any) earth in it; but is a composition of wood, branches, twigs, leaves, and roots of trees, with grass, straw, plants, and weeds; and lying continually in water makes it soft and easy to be cut thro' with a sharp peat-spade. The colour is of a blackish brown; and if it be chewed between the teeth it is soft, and has no gritty matter in it, which the clob has. It is indeed of a different consistence in different places, some being softer, and some firmer and harder; which may perhaps arise from the different sorts of trees it is composed of.

To get at the peat, they first dig up the surface of the ground till they come to the clob, throwing the earth into the empty pits, from which they have already cut out the peat: they then dig up the clob, and either sell it to the poor for firing, or lay it in heaps, to burn to ashes, to be sold to the farmers. Then they cut out the true peat, with a peculiar kind of spade, in long pieces, vulgarly called long squares, about three inches and a half broad every way, and four feet long, if the thickness of the peat will allow that length: and as they cut it out in long pieces, they lay them in a regular order carefully, in rows upon the ground, to be dried by the sun and wind. If the peat be thick, when they have cut one length of the spade for some distance, they return again, and cut down another length of it (or four feet), and so on, till they reach the gravelly bottom, if they can sufficiently drain it of the water, which continually comes in, tho' proper persons are employed to pump out as much of the water as they can all the time. As the peat dries, and is turned by persons appointed for that purpose, to dry it the better, it breaks into smaller lengths, and then it serves not only the poor; but many other persons, for firing, and gives a good heat. It is sold for about ten shillings a waggon-load, delivered at their houses in the town. The ashes also prove very good manure for both grass and arable land; and the farmers give from four pence to six pence a bushel for them, which renders this firing very cheap.

Great numbers of trees are plainly visible in the true peat, lying irregularly one upon another; and sometimes even cart-loads of them have been taken out, and dried for firing: but the nearer these trees lie to the surface of the ground, the less sound is the wood: and sometimes the small twigs, which lie at the bottom, are so firm, as not to be easily cut thro' with the usual peat-spade. These trees are generally oaks, alders, willows, and firs, besides some others not easily to be known. The small roots are generally perished; but yet have sufficient signs to shew, that the trees were torn up by the roots, and were not cut down, there being no sign of the ax or saw; which, had they been felled, would have been plainly visible.

No acorns are found in the peat, tho' many cones of the fir-tree are, and also a great number of nut-shells. They are all of a darkish colour; and the nuts are hollow within, and some of them have a hole at the broad end.

A great many horns, heads, and bones of several kinds of deer, the horns of the antelope, the heads and tusks of boars, the heads of beavers, &c. are also found in it: and I have been told, that some human bones have been found; but I never saw any of these myself, tho' I have of all the others.

But I am assured, that all these things are generally found at the bottom of the peat, or very near it. And indeed, it is always very proper to be well and faithfully informed of the exact depth and place, where any thing of these kinds is found; whether it is in the earth above the peat, or in the clob; or in the true peat, or at the bottom of it; which will greatly assist us in forming a just judgment of the real antiquity of the things that are found, or at least of the time they have lain there. Besides this, as they formerly used to cut out the peat in large plots here and there, leaving spaces full of peat between those pits (whereas now they draw off the greatest part of the water by pumps, and so clear out all the peat regularly as they go on); so it must be carefully observed, whether whatsoever is found here be dug out of these old peat-pits, or not; for axes, and other things, may have been formerly dropt into these pits, before they were filled up again with earth, and may now be dug out of them again. My father has now in his possession an iron hatchet, not greatly differing from the modern form, which was found lying flat at the very bottom of the peat: it was covered with a rust near half an inch thick, and the handle was to it, which seemed to be of beech-wood, but was so soft, that it broke in bringing it up: but as the person is dead, who found it, I can't say whether it lay in an old peat-pit, or no.

Mr. Osgood found, some years ago, an urn, of a light brown colour, and large enough to hold above a gallon, in the true peat about eight or ten feet from the river, near a mile and a half west of this town, in Speen-moor. It lay about four feet below the level of the ground, and about one foot within the peat; and over it was raised an artificial hill, about eight feet higher than the neighbouring ground; and as the whole hill consisted of both peat and meadow-ground intermixed together, it plainly appeared, that the peat was older than the urn; and that the persons, who raised the hill, must first have dug a large hole in the peat, to bury the urn there, and so formed the hill of the peat and meadow-ground mixed together. Round the hill, where the urn lay, they had made also many half-circular ridges, with trenches between them, one beyond another, in this manner:

Where a is the river, and c the hill; and the half circles shew some of the ridges, the number of which Mr. Osgood has now forgot. The urn was broke by the peat-spade, and it came up only in small pieces, so that nothing was found in it; and no body happened to be there at that time but the peat-cutters.

No coins of any sort have been found in the peat. But there may, perhaps, be a variety of things at the bottom of it: but as the peat is always full of water, which is never quite drained off, so it is not an easy matter to examine the bottom.

I beg leave to assure you, my Lord, that I am, with great respect and esteem,

Your Lordship's most obliged,
and obedient humble Servant,
John Collet.

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XVI. An Account of the Alterations making in the Pantheon at Rome: In an Extract of a Letter from Rome to Thomas Hollis, Esq; Communicated by John Ward, LL.D. R.S. Vice-Præs.

Read Mar. 3, 1757.

A Project was lately laid before the government by Paolo Posi, an architect, for modernizing the inside of the Pantheon, and unfortunately approved. In consequence of which, the dome has been already cleaned, and rough cast; and the remainder of the lead taken away, which served as a lining to the silver work, that originally covered it. The vestiges of the cornices, and other ornaments of the silver work, were still discernible in the lead, which was fastened by very large iron nails. All this was effected by a moveable scaffold, that was fixed to the bronze cornice of the open circle above, whereby the temple is illuminated, and descended to the cornice of the Attic order, being as curious in the contrivance, as detestable for the purposes intended by it. It is true, we could not before see the dome in its pristine glory; but we had the satisfaction of viewing the traces and remains of what it had been. Nor could the adepts in architecture sufficiently admire the skill and sagacity of the builder, who, composing it of a number of small arches, which together formed a kind of net-work, and filling up the intervals between with pumice-stones and mortar, gave it that strength and lightness, whereby it has probably stood so many ages.

The evil would be comparatively small, had the project extended no farther, than what has been related; but they are now busy in removing the Attic order, to make room for a new invention, suitable to the trifling taste, which at this day prevails. And not content with that, they think of taking away the ancient pavement; and, what is still worse, its peculiar beauty, the open circle at the top, to place a lanthorn instead of it, as is usual in modern cupola's.

You had the good fortune, Sir, to view this remarkable temple, in that state, wherein it was left by the ancient barbarians: but those, who see it hereafter, will find it in a much more deplorable condition, stripped of its precious marbles and ornaments; and so disguised by modern alterations, that the noble form given it by Agrippa will be no longer distinguishable.

It is said Il Signor J.B. Piranesi, the architect, who published the antiquities of Rome, and divers ingenious works of that kind, has taken accurate plans of the Attic order, and every other particular relating to it. These he proposes to engrave and publish, with exact explanations annexed to them; together with a plan of the whole, as he believes it appeared in its original splendor and perfection; that posterity may not be deprived of informations, which are of so great benefit and importance to all lovers of architecture. It is also said, that the engineer [carpenter], who invented the scaffolding, has made an exact model of it for him; which he intends to publish as a part of the work before-mentioned.

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XVII. An Account of a new medicinal Well, lately discovered near Moffat, in Annandale, in the County of Dumfries. By Mr. John Walker, of Borgue-House, near Kirkudbright, in Scotland.

Read Feb. 10, & Mar. 3, 1757.

THIS mineral spring was found out by one Mr Williamson, a few years ago, when he was overseeing a mine, which was at that time carrying on in its neighbourhood. It is situate about four miles distant from Moffat, in the bottom of a deep scar, which is on the west side of a large mountain called Hartfell, from which it has acquired the name of Hartfell-spaw. This scar is a part of the mountain, thro' which a small stream of water has worn its way to a considerable depth; by which it has laid open, and exposed to view, the strata of the earth on each side: and in the bottom of this scar, and near to the brink of this small brook, the mineral water springs up.

When I saw it, it consisted of two springs, which were very well ordered by Mr. Williamson, so as to run from two wooden spouts, immediately at their rise out of the earth; which indeed must be of very great advantage to all mineral waters; and I am persuaded there are many, whose medical qualities are greatly impaired by falling into reservoirs, and continuing in them for some time after they spring from the earth. The one of these springs was situate about ten or twelve yards farther up the brook than the other; and they were then distinguished by the names of the upper and lower spring: but I have been since informed, that their situation is now altered. Each of these springs did at that time run nearly the same quantity of water, which, as I thought, was above an English quart in a minute, and that during a season of very dry weather.

As there are many instances of mineral waters springing out of the earth very near each other, which at the same time are impregnated with very different principles; it therefore seemed not at all improbable, that as these waters did appear to run, for some part of their course, in different channels, they might in some respects be different from each other. And this suspicion I found not to be altogether groundless with regard to these springs, as will be shewn afterwards. For which reason it may be observed, that the following trials were all made upon the water of the upper fountain, except where the other is particularly mentioned; and also that they were made within 24 hours after the water was taken from the spring, being carried to Moffat in bottles carefully sealed.

According to what may be inferred from the following experiments, it may be premised, that this water appears to contain in it a large proportion of iron, but in two different forms; and an aluminous salt, which is conjoined with a terrestrial principle.

As the contents of several mineral waters have been the cause of many different opinions, and of great disputes among physicians and chymists; as the inquiry I made into the principles of these waters, which I am now considering, was not performed with that nicety and exactness I could have wished; and as I am persuaded, that to dogmatize in any branch of philosophy can never tend to its advancement; I shall not therefore pretend to determine with certainty in any part of this subject, where the contrary opinion can be admitted with the least degree of probability. These trials are indeed but few and imperfect, and are no-way sufficient to form an exact account of this mineral water; yet I believe they may afford some conclusions, which may be serviceable in compiling a more compleat history of it. They render it pretty evident, that the above-mentioned principles are contained in these waters: and tho' I will not pretend absolutely to exclude all others, yet I must say, that, by what inquiry I made, I could not observe them to be in the least impregnated with any other kind of mineral substance.

After a good deal of observation upon the water of this Spaw; and after many fruitless attempts, which I have at different times made upon several other waters of the chalybeat kind in Scotland, in quest of the volatile spirit, which has been commonly attributed to them; I must own, that I have been induced to think, that there is no such thing exists in these waters at all. What has been generally called the spirit of steel waters, seems to me to be very unintelligible; altho' the existence of it in these waters has been asserted by all the writers on this subject, which I have yet had occasion to see. The spirit of a mixed body is commonly taken to be a subtile, penetrating, light, and volatile substance, more susceptible of motion than any other of its parts, and most easily separable from them by avolation. But that any chalybeat water contains such a substance, I think has never been made evident, unless where the water has been found to be impregnated with some other mineral principles. Some steel waters, I believe, contain a large proportion of air, whose elasticity may occasion it to break forth with an explosive force; some others there are, which contain a volatile and sulphureous halitus; and to one or other of these two causes, or to some other mineral principle, I think most of the phænomena may be referred, which have been attributed to a ferrugineous or vitriolic volatile spirit.

As the first thing observable in a mineral water is its outward form, we must therefore take notice, that the water of this Spaw equals the clearest spring-water in transparency; and is likewise as free of any colour or odour: yet its taste is very strong, and may be discerned to be compounded of a sweet, subacid, and astringent taste. Its sweetness and acidity appear sensibly to arise from alum; and its high styptic and astringent taste does as evidently proceed from that mineral salt, joined with some earthy or ferrugineous parts. I must likewise observe, that when I first compared the taste of these two springs, I could plainly discern, that the water of the lower spring was more acid, and less astringent, than that of the upper one; and, on the contrary, the water of the upper spring seemed more astringent, and less acid. This induced me to think, that the mineral parts, which caused the acid and astringent tastes, were mixed in the waters of these two springs in different proportions. And what I observed of them afterwards still confirmed this conjecture.

But, in order to give some evidence for the existence of the above-mentioned minerals in the waters of these springs, we shall consider them separately, by relating the experiments, which seemed to indicate, that they are contained in these waters in a very considerable proportion, and by offering some conclusions, which may be reasonably drawn from them.

And as the first trials were made in quest of iron, it may perhaps be most proper to consider it in the first place.

Experiment 1. Some pieces of galls being added to equal quantities of the water of the two springs, an exceeding deep and bright blue colour was immediately produced in the water of the upper spring, which in a little time turned to a perfect black. The water of the lower spring, tho' indeed it was turned of the same colour, yet was not of so deep a shade, but was somewhat lighter than the former. The tincture of galls caused the same appearances.

2. A tincture of balaustine-flowers produced the above blue colours in both waters.

3. A quantity of the water being thoroughly tinged with galls, was allowed to stand 24 hours: being then filtrated thro' brown paper, the water, tho' almost quite colourless, would not again receive any tincture with galls.

4. After elixation the water became of a turbid yellow colour with ochre, and afforded very little tincture with galls.

5. A solution of sal Martis, chemically prepared, being mixed with galls, immediately turned of a bright dark blue colour, exactly similar to that produced in the water.

6. A solution of common and rock alum was no-ways changed in its colour with galls.

7. A solution of sal Martis and alum being mixed in equal quantities, the mixture was turned of a bright blue colour with galls; yet not of so deep a hue, but of a more diluted colour than the solution of sal Martis, without alum.

From these experiments we must first of all observe, that the colour, which these waters afford with galls and pomegranate-flowers, is very uncommon. The more iron, that any mineral water contains, it will afford the deeper colour with such astringents: but tho' I have tried this experiment upon a great many of the ferrugineous waters in Scotland, and also upon the waters of some of the foreign Spaws, I never observed one, that afforded so deep a colour as this, which we now consider. Some of the weakest of them gives only a red or faint purple tincture, and the strongest only a deep purple: but I never saw or heard of any chalybeat water, but this, either in Scotland or elsewhere, that afforded an intense black and inky colour with galls. From which, I think we may venture to conclude, that the water of this Spaw contains a far larger proportion of iron than most, or perhaps than any, other chalybeat water hitherto discovered: and for this reason, I dare say, it will likewise be so much the more preferable to most others in medicinal virtues; which has indeed already appeared by many surprising cures it has performed, and which, I am persuaded, will more fully appear, when its medicinal effects shall be better known.

There must needs be a very great quantity of iron in this water, when it yields as deep a colour with galls as a strong solution of sal Martis. I was indeed at first apprehensive, that this perhaps might not be owing so much to a large and uncommon proportion of chalybeat parts, as to the commixture of alum, which I judged to be in the water. But we see the contrary appears by these trials: for alum of itself affords no tincture with astringents, and, instead of rendering a solution of sal Martis with galls of a more intense colour, rather makes it lighter and more diluted.

We see here, that the ferrugineous matter is intirely separated from the water by an infusion of galls. The like also happens by elixation; after which it is almost deprived of its tinging quality. Yet other chalybeat waters lose this quality by much less degree of heat.

As there is an ochrous earth separated from all steel waters, when exposed to the air, which subsides to the bottom, and a metalline scum or cremor, which swim on their surface; we shall next consider the appearances, which they make in this water.

Exp. 8. A solution of saccharum Saturni being dropt into common spring-water, left the upper parts of the water clear and colourless, but formed a lactescency towards the bottom. The same solution being added to the mineral water, soon turned it of a turbid yellow colour, which afterwards subsided, and formed a deep yellow cloud in the bottom of the glass; and below this yellow sediment there adhered to the bottom of the glass a whitish substance, which I took to be the metalline parts of the saccharum Saturni separated from the purer parts of the salt, which were still suspended in the water, and which made it of a muddy whitish colour.

9. Forty drops of oleum tartari per deliquium being added to an ounce of the water, made it of an uniform light yellow colour; but in an hour afterwards there were many small yellow terrene nubeculæ formed in it. These the next day were more conspicuous, being thoroughly separated from the water, and precipitated to the bottom, leaving the water quite clear, as it was before the mixture. A small quantity of this limpid water being taken, it would afford no tincture with galls. It was then all poured off, except so much in the bottom of the glass as contained the above-mentioned clouds: to this there were some galls added, which in half an hour turned these clouds from a light yellow to a deep red colour, but did not change the colour of the water, in which they swam.

10. Immediately after the affusion of ol. tart. p.d. to the water, galls were added to the mixture, which tinged it of a deep and bright red colour. After standing for some time, there were red clouds precipitated to the bottom, and the water continued of a dusky opake red colour.

11. There is a small brook, formerly mentioned, which runs near by these springs; into which the water, that flows from them, is discharged. I observed the stones and channel of this brook all tinged with ochre of a deep yellow colour, so far up as the water of these springs flowed into it; but the channel, which the mineral water ran over before it was mixed with the water of the brook, was very little or nothing discoloured with ochre. As I conjectured what this was owing to, I afterwards took two equal quantities of the mineral water, into one of which I put an equal quantity of common water. In two hours the mixture became less transparent, and appeared yellowish, while the simple mineral water retained its clearness. Next day there was much ochre separated from the mixture, which subsided to the bottom of the glass: but the unmixed mineral water remained still clear and colourless, as at first.

All chalybeat waters separate their ochrous parts, when exposed some time to the air; but this separation is made sooner by the commixture of several kinds of salts. Thus we see the ochre in this water is immediately separated and precipitated by the solution of saccharum Saturni.

The oil of tartar causes a precipitation of these ferrugineous parts in the same manner. Which parts must be the sole cause, that the water receives a tincture from galls; since, after they are precipitate, it loses that quality, which they notwithstanding retain even after they are separated from the water. This precipitation of the ochrous parts of the water were the only visible effects that I could perceive to follow from the affusion of the ol. tart. p.d. I remember indeed, when I was at Moffat, I saw the manuscript of Dr. Horsburgh's experiments upon this mineral water; which appeared to be very accurate; and which I understand are since printed, in a volume lately published by the Philosophical Society at Edinburgh. Amongst these I observed one, which I thought so very remarkable, that I particularly adverted to it. It was the effects of the affusion of ol. tart. p.d. to the water, producing in it clouds, or a coagulation of a green or grass-green colour. I think these were the words; and I own I was something surprised at them. A solution of vitriolum Martis, mixed with this alkaline oil, does indeed produce a green coagulum: but I could scarcely think, that this, or any other chalybeat water, contained so large a proportion of that vitriol, as to be sufficient to produce these effects, when I considered, that so many writers, which I had seen, upon this subject, have all failed in their attempts of extracting a conspicuous martial vitriol from such mineral waters. I had tried this experiment upon four or five chalybeat springs in Scotland, and likewise upon the Spa and Pyrmont waters, which had been well preserved; but there never resulted any such effects from the mixture of these with oil of tartar, as are related in the above experiment. All the alteration it produced in these waters was the precipitation of an ochrous earth, but without the least appearance of any green colour. As I looked upon this as a leading experiment in the history of vitriolic waters; as I had often tried it, and as often seen the green coagulum produced with the solution of the factitious vitriol, and never could observe it produced in any of the above water; I began to suspect, that these waters were either not possessed of a vitriolic salt at all, or else, that it was in some respects very different from the factitious vitriol. For these reasons, Dr. Horsburgh's experiment appeared very extraordinary; tho' at the same time I was greatly pleased, that I should have the opportunity of repeating it, and of observing those phænomena in this ferrugineous water, which I had sought for in vain in several others. But when I came to make the trial, I was yet more surprised, when I found it misgive, and that the ol. tart. p.d. produced no green colour or coagulum in this mineral water, nor caused any other alteration in it, than the separation of a large quantity of ochrous earth of a yellow colour, exactly the same with what I had observed in the other steel waters. This failure made me immediately conclude, that I had somehow or other committed an error in the experiment: and tho' I was pretty sure, that the mineral water, which I had used in it, was quite fresh, yet I could not be so positive as to the oil of tartar, which I suspected to have been long kept. Yet that this could have been the cause of my being so unsuccessful, I could scarcely believe, tho' indeed I could assign no other. I was sorry, that I had not afterwards an opportunity of repeating this experiment with more accuracy, from which I might have expected to reap more success, as it is perhaps one of the most consequence, that can be performed on this mineral water, as it is capable of demonstrating the existence of a substantial vitriolum Martis in it; which is more than has been hitherto done, or perhaps ever will be done, concerning any one of the vast number of chalybeat waters, which have been yet discovered.

When galls are added to the water, at the same time with oil of tartar, instead of its deep blue colour, it affords only a red tincture.

It appears from the 11th experiment, that an addition of common water causes the mineral water to precipitate its ochre; and the reason of this is obvious: for if these ochrous parts be altogether terrene, as they appear to be, and exist in the water unconnected with any other principle, then it must happen, that as these parts are uniformly diffused thro' the water, in which they are suspended as in a menstruum; by the addition of common water, this menstruum being diluted, the cohesion of these terrene parts must be thereby weakened, and their contact destroyed; so that their menstrual equilibrium being thus taken off, they can be no longer supported in the fluid, but must be precipitated by the force of their own gravity.

Exp. 12. When the water was exposed for some days to the air, there was a cremor separated from it of a shining chalybeat colour. This, like other kinds of cremor, takes a considerable time to compleat its intire separation from the fluid, out of which it is expelled: for when it was despumated, a new cremor always succeeded, until the whole quantity, which the water contained, was exhausted.

13. When this cremor first appeared on the water, it was of a faint blueish colour; but as it increased, it changed into a deeper and more bright shining blue: and, after longer standing, it became blotched with various colours, as red, orange, yellow, green, blue, purple, and violet.

14. A quantity of the water being put in a gentle heat, this cremor was quickly separated from it, and appeared on the surface of the water. A like quantity of the water, with its cremor already upon its surface, was put over a gentle heat, which by degrees broke the cremor into very small parts; but whether they did evaporate, or precipitate in the water, I could not be certain. But, by other trials, this cremor was found to have a great degree of fixity, bearing a considerable heat without avolation; yet not without the appearance of some of its parts flying off, altho' most of them were fixed; because what remained lost its fine colours, and was changed into a shining chalybeat colour.

15. The water of the lower spring afforded a much less quantity of the cremor, than the water of the upper spring. It took also a longer time to separate, was of a blueish colour, and had not the vivid colours, which the water of the upper spring shewed.

16. When ol. tart. p.d. and spirit of sal ammoniac were added to the water, it did not separate its cremor.

This cremor, which is separated from the water, is the same with that, which appears on the surface of a solution of vitriolum Martis, when exposed for some time to the air; and an infusion of iron in common water also emits a cremor of the same kind. I remember, as I was once carefully observing a large glass full of chalybeat water, which contained much of this cremor; soon after it was exposed to the air, I observed a tenuious blueish vapour rising in the parts of the water next the surface, which very much diminished its transparency; and by degrees this vapour was emitted by the lowest parts of the water: but as the cremor increased on its surface, the water became gradually deprived of the blueish tincture, which it received from this halituous body; which was apparently nothing else but the parts of the cremor separating from the water, and ascending upwards. From whence we may conclude, that this cremor consists of the very finest part of iron attenuated to the highest degree.

It has been the opinion of most naturalists, that these kind of mineral waters do abound in sulphureous parts. This they have conjectured from the foetor, that often attends them. But in what quantity or form these parts exist in the fluid, or by what means they can be rendered conspicuous, has not as yet been sufficiently determined. Yet, I think, we may suspect some of the parts of this cremor to be sulphureous. They are volatile, and, being heated, do fly off from the pure metalline parts, which being more fixed, are thereby left destitute of those vivid colours, which they enjoyed from the sulphureous parts. These are evident marks of sulphur, and are altogether analogous to some other appearances of that mineral. Another observation tending to support this is the want of those vivid colours in the cremor, which appears on an infusion of iron; the reason of which seems to be the loss of the sulphureous parts of the chalybeat minerals by avolation, during the operations of the fire, which they undergo in refining.

It appears from the fifteenth experiment, that the water of these two springs contains a very different proportion of this cremor: and from the last, that it is precipitated along with the ochrous parts, which happens upon the affusion of these alkaline liquors.

The next trials were in quest of alum.

Exp. 17. A quantity of the water being kept for some time in a boiling heat, and after it was cool being filtred quite clear from its ochrous matter, it still retained a subacid and aluminous taste in a very strong degree.

18. To an ounce of common spring-water there was added two gutts of fresh sweet milk. This mixture being shaken, the milk mixed intimately with the water, without any kind of coagulation.

19. The same experiment being made with the mineral water, the milk, upon its affusion, was so curdled, or separated into clouds, that the greatest shaking could not mix or incorporate it with the water.

20. This experiment being also made with a weak solution of alum in spring-water, its effects upon the milk were not in the least different from those of the mineral water.

21. And the same trial being again repeated with the water, when boiled and filtred from its ochrous parts, the milk was in the same manner coagulated as before elixation.

22. One part of sweet milk being added to four parts of the mineral water, the milk subsided, and formed a cloud in the bottom of the glass, leaving the upper parts of the water clear. This mixture being heartily shaken, the milk mixed so well with the water, that it appeared to be but a very little curdled.

23. When a larger quantity of milk was added to a smaller quantity of water, and even when equal parts of the milk and mineral water were mixed and shaken together, there could be no curdling or coagulation observed.

24. An equal quantity of the water and milk being boiled together, the greatest part of the milk was coagulated into a thick white curd; and the remainder, with the mineral water, turned of a pure white milky colour, which drank like whey, and was very agreeable.

25. Eight gutts of sweet milk being added to four ounces of the water, and the mixture boiled, part of the milk was thereby curdled, and swam upon the top of the water. The ochrous parts of the water were likewise separated, and falling to the bottom, their colour did not appear of a clear yellow, as usual, but was something milky.

All these experiments strongly indicate the existence of alum in this water. It retains its aluminous taste, and coagulates milk, after the chalybeat parts are almost all expelled by elixation. The coagulation of the milk demonstrates an acidity in the water, and the other appearances shew that acidity to be owing to an aluminous salt.

It appears, that the milk requires a large quantity of the water, to make a sensible coagulation in it: for, in the 22d experiment, one part of the milk being added to four parts of the mineral water, the coagulation was scarcely discernible: and in the 23d, when an equal or larger quantity of milk was added to the water, the coagulation was not at all observable. I have heard it confidently averred, that this mineral water did not at all curdle milk; which, I suppose, has been thro' a mistake in the experiment, in adding too large a proportion of milk to the water: for in this way the coagulation cannot be observed.

I imagined, that when the water was boiled with milk, the mixture would have become of a muddy yellow colour, by the separation of the ochre: but it did not even appear, that the ochre was at all separated from the mixture, as it is from the water when boiled by itself. On the contrary, not only the coagulum, but also the liquor, was of a pure white colour, and of a pleasant taste: and this makes me think it worth the inquiring into, whether or not the water does retain its medical qualities after it is prepared in this manner with milk? For, if it does, such a preparation might certainly be very serviceable in many cases.

These experiments, which we next relate, do not only ascertain the existence of alum in the water with greater certainty, but also, that there is a particular kind of earth conjoined with this salt.

Exp. 26. An English quart of the water being kept boiling for a quarter of an hour, it turned thick, muddy, and yellow, by the separation of its ochrous parts; and, being set to cool in a clean bowl, the next day all the ochre was subsided to the bottom, from which the water was carefully filtred: whereby it became almost as clear and limpid as before the elixation, retaining a sharp aluminous taste, but was deprived of the strong ferrugineous taste, which it had at first. This water was again boiled; by which means it was again turned a little yellow, by the separation of some more ochre. It was therefore again filtred, and rendered clear, and its aluminous taste was stronger than before. After this filtration, the water was evaporated in a sand-heat to about a sixteenth part of the original quantity, and then it tasted like a strong solution of alum joined with a small degree of a chalybeat taste. And this being totally evaporated in a glass, there adhered upon its sides a pure white salt; and a larger quantity of the same salt remained in the bottom of the glass, which was not so white, but more impure than the former, and of a brown colour.

27. This salt, thus procured from the water, being mixed with distilled vinegar and spirit of vitriol, there was not the least effervescence produced.

28. Some of the brown-coloured salt being put upon a red-hot iron, it did neither sparkle nor decrepitate; but was turned into a blackish cineritious substance, which in a short time became a white calx. And tho' some of the salt was put upon the iron finely powdered, yet it concreted, and run together in a cinder, whose cohesion was afterwards destroyed when calcined by a further degree of heat.

29. As I was accidentally deprived of the opportunity of obtaining crystals of this salt, which would have been the best means of knowing to what species it was to be referred; I dissolved the whole mass in a small quantity of spring-water, and, by filtrating this solution, I obtained a large proportion of fine earth of a brown colour.

30. This solution of the salt afforded a deep blue tincture with galls.

31. The same solution, being mixed with syrup of violets, became of a reddish colour.

32. Saccharum Saturni being added to the solution, precipitated a thick lactescent cloud.

33. Ol. tart. p.d. being also added to this solution, it caused no visible effervescence, yet raised some bubbles of air, and caused a coagulation of many small brown terrene nubeculæ in the water; which, after standing some time, subsided to the bottom, and left the water clear.

These experiments do plainly evince, that this water contains an aluminous salt, conjoined with a fine terrene substance, which is probably a part of the matrix, from whence the salt has been formed.

This salt gives no signs of any alkaline principle; but, on the contrary, of an acidity, as its solution reddens with syrup of violets.

With this salt there are also intimately conjoined some very subtile chalybeat parts, which are not separable from it by elixation or evaporation.

Alum is distinguishable from all other mineral salts, by liquifying and bubbling upon a red-hot iron, and turning into a white calx. But this could not be well expected from this aluminous salt, which we had extracted from the water, because it was extremely foul, by being combined with so large a proportion of earth; which earthy parts were the occasion of turning the salt of a blackish colour upon the iron. However, we see it turns white by a further degree of heat. But if the salt had been dissolved, filtrated, and crystallized, till it had been purified and freed from this terrene matter, it would then certainly have had the same appearance upon the red-hot iron, as a pure aluminous salt. Again, as it is peculiar to an aluminous salt to liquify in some degree with fire, so we see, that this was evidently the case of this salt. Its eliquation indeed could not be so remarkable, as in pure alum, because of its being mixed with so much earth; but that it did liquify in some degree is plain, because the whole mass of salt and earth, even when reduced to a powder, ran all together like a cinder.

The experiment upon the solution of this salt with ol. tart. p.d. is also a further proof of what we have already asserted: for tho' there was no visible effervescence, yet the bubbles of air shew, that there was an intestine conflict of the oil with the acid principle in the solution; which being absorbed by the alkali, the earth was precipitated, to which it formerly adhered.

The two next experiments were made in order to discover, whether an acid or alkaline principle prevailed in the water.

Exp. 34. Forty gutts of the syrup of violets being added to an ounce of the water, the mixture became of a bright sea-green colour.

35. A quantity of water being kept boiling for five minutes, and afterwards allowed to stand till it became clear, was carefully filtrated from its ochrous sediment: after which, upon its mixture with syrup of violets, it turned of a faint reddish colour.

From these experiments we infer, that this mineral water contains both an alkaline and an acid principle; the former consisting of the ochrous and ferrugineous parts, which are separated from the water by elixation; and the latter of the aluminous salt, which remains in the water after elixation.

The following trials were made in order to know what effects are produced in the water by being exposed to the air; and in what respects the waters of the two springs differed from each other.

Exp. 37. An English quart of the water of each of the springs being fully exposed to the air in two China bowls, the next day that of the under spring was neither altered in its taste, colour, or transparency, nor in any other shape whatever; but that of the upper spring appeared of a yellowish colour, altho' it was clear and transparent as the other.

On the second day the taste of the waters scarcely appeared to be any way diminished. No sensible change could be observed in the lower water; but the upper water was become more yellow than it was the day before, yet without any loss of its transparency. They both tinged of a deep blue colour with galls; which tinctures appeared equally deep and strong, as they did before the waters were exposed to the air.

The third day the lower water appeared clear and colourless as before, only its surface was covered with a few small spots of cremor. The upper water appeared more yellowish than formerly, and its surface was almost wholly covered over with the cremor. They both afforded a tincture with galls, which was not sensibly different from what they gave before their exposure.

On the fourteenth day the water of the under well had precipitated a yellow ochrous sediment, but the other water a more considerable quantity. A large quantity of cremor continued also to swim upon the surface of the upper water, but there was very little separated from the water of the under well. Both waters being now tried with galls, instead of the deep blue colour, which they did formerly exhibit, they now became only of a deep purple colour.

On the twentieth day the visible appearance of both waters was the same as when last observed.

On the thirty-eighth day they both afforded as deep a purple colour with galls, as they did three weeks before; and during that time also they had not precipitated any more of their ochrous parts, nor suffered any other sensible alteration.

The water of the upper well being filtrated from all the ferrugineous matter, which it had separated during these thirty-eight days, was rendered almost as limpid and clear as when newly taken from the well: but, being boiled for some time, it became of a turbid yellow colour; and being allowed to stand, it again precipitated abundance of an ochrous sediment; and being filtrated, and mixed with galls, it received a faint purple colour of a blueish hue.

38. A bottle of the water of each of these springs, being carefully sealed, carried to Moffat, and kept for two months, suffered not the least alteration during that time, but was as fresh as when immediately taken from the fountain. And I am informed, that after it is carried to Edinburgh, and to places at a greater distance, it will keep a much longer time without being any way spoiled.

I believe it will appear from these observations, that this mineral water continues longer intire, and particularly that it retains the quality of tinging with galls longer, than most others of the chalybeat kind: at least, of a great number, which I have seen described, I do not remember one, that retains it near so long, when exposed to the open air. Many of them lose this quality intirely in a few hours; and it is greatly impaired in the same time, even in those which retain it longest. But this water, we see, remains exposed to the open air for days, without almost any alteration. This may perhaps be owing either to the larger proportion of ferrugineous parts, with which it is impregnated; to their being attenuated to a greater degree; or to their more perfect commixture with the water, by means of the aluminous salt. The longer time, that any mineral water does remain intire, without any separation of its mineral parts; or the longer it retains the same form, which it has when newly taken from the spring; the more perfect is the commixture of these parts with their fluid vehicle: and I believe, upon that account, will be more effectual for medicinal uses: for which reason, I suppose, these waters may prove a more beneficial medicine, than any others of the ferrugineous kind, whose mineral contents are not so intimately commixed with the aqueous fluid.

As these waters are so long in separating their mineral contents, they appear particularly well adapted for being transported to distant places: for by this quality they are fitted to undergo a long carriage, and to be kept a considerable time, without any diminution of their medicinal virtues. It must also be noticed, that the water of the under well is by much the best of the two for carriage, or for being long kept, as it is longer in separating its mineral contents than the upper one.

From these experiments it is evident, that there is a considerable difference betwixt the waters of the two springs. The upper one contains a much larger quantity of ochrous earth, and metalline cremor, than the under one; which is the reason, why it yields a deeper colour with galls, as may be observed in the first experiment. I suspected, on the other hand, that the under water contained a greater proportion of alum, than the water of the upper spring; but this I cannot affirm, as I find I had neglected to make the experiment, which would have determined whether it be so or not. Tho' the mineral contents of these two waters be similar, yet, if they be thus mixed in them in different proportions, this must certainly create a difference between them, which deserves to be attended to, as it may be sufficient to disallow of their being used promiscuously, since their medicinal effects may be thereby different.

But now, to sum up the evidence, which these experiments, taken all together, do afford, concerning the mineral ingredients of this Spaw; I think they determine, with some degree of certainty, that it contains two different principles of iron, both of which are fixed. The one, which is the ochrous earth, is a true minera ferri, and, altho' it be a crude mineral, exists in the water in a very fine and subtile form; the other, which is the cremor or pellicle, whose parts are also extremely attenuated in the water, appears to be iron, not in its mineral, but in its metalline form, and, when thrown up upon the surface of the water, shews itself like an extreme thin lamina of that metal. There seems also to be some small proportion of sulphur joined with the metalline cremor. The other mineral ingredient, which enters into the composition of this Spaw, is a considerable proportion of an aluminous salt, which is conjoined with a small quantity of a light brown-coloured earth (probably a part of the matrix whence the salt is formed), and still more intimately connected with some of the chalybeat parts of the water, which are not separable from it either by elixation or evaporation. Whether these be saline or terrestrial, I cannot determine.

Having thus endeavoured to discover, by some plain and simple experiments, the mineral principles, with which this medicinal water is impregnated; I shall now only add some observations, with respect to the origin of steel waters, and particularly of this Spaw, whose origin, I think, is thereby discovered and ascertained in a very obvious manner.

Among several things, that are still deficient in the history of mineral waters; an exact knowlege of their origin seems to be the chief; that is, from what fossils, and in what manner, these waters do acquire the mineral substances, with which they are impregnated. As this happens in the bowels of the earth, and is therefore far removed from our view, it is not surprising, that there has been so little discovered concerning it; tho' indeed there have been many elaborate hypotheses framed in order to account for it.

The writers on mineral waters have been of very different and opposite opinions concerning their origin. They have disagreed widely amongst themselves; and I very much suspect, that the accounts, which most of them give of this matter, are not agreeable to truth: particularly with respect to chalybeat waters, I have seen none, who have given a satisfactory account of their origin. They have all agreed, that iron, or the vitriol of that metal, does exist in mineral waters; but they have never yet agreed, how they came to exist in them, or in what manner mineral waters come to be imbued with these fossils.

Some of the more ancient writers cannot comprehend, how simple water should be intimately impregnated with so many different kinds of minerals, except by the means of some powerful agent. And as they thought nothing more proper for communicating and mixing mineral substances with water, than violent heat, they therefore termed all mineral waters, of whatever kind, by the name of thermæ. They saw some spring from the earth extremely hot, others moderately hot, others tepid, others excessively cold: they concluded from this, that all such various degrees of heat in these waters were owing either to the different degree of subterranean fire, which they had undergone; or else to the great distance, which some of them had run in the earth, after they had been sufficiently heated. They therefore maintained, that those waters particularly termed acidulæ (the greatest part of which are impregnated with iron), or those, which, tho' intensely cold, contained a large proportion of mineral matter, had in some part of the earth been impregnated with it, by means of an intense heat, which they had been gradually deprived of by a long passage thro' the colder parts of the earth.

Some naturalists again, of a later date, having exploded the former notion as chimerical, have thought, that a vapour rising from vitriolic minerals, and mixed with the neighbouring streams of water in the bowels of the earth, has imbued them with some of the parts, and with the properties, of vitriol.

Others are of opinion, that the exhalations of vitriolic minerals, passing thro' the cavities of the earth, are there condensed by the subterraneous cold into a limpid fluid, containing the very finest parts of that mineral salt: which fluid, mixing with the præterlabent streams of water, and issuing out of the earth with them, produce those mineral springs called vitriolic.

The last opinion I shall mention on this subject, and which indeed appears the most plausible, is of those, who think, that the iron is corroded and dissolved in these waters by means of an acid: for, as they imagine simple water incapable of doing this, they suppose, that it is first imbued with an acid in the bowels of the earth; and then, by the corrosion of the chalybeat minerals, thro' which it runs, it comes to be impregnated with them. I once received this opinion, as the most probable I could then observe, concerning the origin of these springs: yet not as being satisfactory; for there are many objections against it, which it is difficult either to elude or to answer.

The supposition of an acidity in ferrugineous waters, I thought but ill confirmed, because, upon trial, they discover no vestiges of it, but rather appear to be alkaline. Besides, in considering the causes of mineral waters, it seems more probable, that whatever minerals they contain, they must be such, as can be received or extracted by common water in its passage thro' the earth, by solution, abrasion, or the like simple operations; and in this way alone I think we may come to account not only for the commixtion of the saline and terrene minerals, which are found in medical waters, but likewise of those, that are metalline or sulphureous; for which simple water, at first sight, may perhaps seem to be an insufficient solvent.

It was this notion, that first induced me to make trial upon various mineral and metallic bodies, in order to know how far they could communicate their virtues to common water by infusion. I thought this might throw some light upon the origin of mineral waters; yet, tho' I made a great many experiments of this sort, and particularly upon several kinds of native chalybeat minerals, I was as little satisfied concerning their origin as before. I at length, however, met, by accident, with what I had inquired after with so little success.

As I happened to be at a gentleman's house near Edinburgh, in whose estate there was a great deal of coal, and who was at that time working a level or adit, in order to drain off the water, I observed, that the current of water, which flowed from this level, separated a great quantity of ochre, and, emptying itself into a river soon after it came from the entry of the level, tinged all the stones and the channel of the river, for a good way, of an ochrous colour. The taste of this water was exactly like that of a common steel Spaw; and it afforded a purple colour with galls[55]. As I knew, that this water flowed off a great body of coal, I often infused that fossil, taken from the pits near this level, in common water; but the infusions never yielded any tincture with galls. I tried in the same way another mineral, that the miners call blaes; which is a cliffery stratum of a blueish colour, that often lies both above and below the coal: also another fossil of a brown colour, which is very ponderous, and is called by the miners dogger; a thin seam of which often lies in the midst of the coal. However, neither of these would afford an infusion, that would tinge with galls. At last I got another mineral out of these coal-pits, which is sometimes found amongst the coal, but is not so frequent as any of the former; and this fully answered my expectation. It is found either in round or broad pieces, is exceeding ponderous, and of a shining yellow colour, and is called by the miners brass lumps. When I infused this mineral for a short time in common water, it communicated to it all the properties of a steel Spaw; its taste was exactly the same; and it received a tincture from galls, which was of a more diluted or intense purple, according to the proportion of the mineral added to the water, or to the time of the infusion. This simple experiment does therefore clearly discover to us the origin of steel waters, and the manner, in which they are impregnated with their mineral contents in the bowels of the earth.

This observation, which I had made concerning the origin of steel waters, led me, when I first visited Hartfell-Spaw, to inquire into the adjacent fossils: which was the more easily done, as the strata of the earth about the well, for a considerable depth, are exposed to view. After some search among these, I found a stratum of cliffery rock, about three or four feet thick, of a grey colour, and, I think, about twenty paces from the spring. In some of the hollow places of this rock, where the rain and wind did not reach, I observed a white saline efflorescence on its surface, which when I had taken off and tasted, I concluded, from its styptic and chalybeat taste, that it was a native vitriolum Martis, notwithstanding its white colour; but I found it, upon trial, to be alum, having some fine attenuated parts of iron conjoined with it, and the same salt with that contained in the Spaw water.

Having taken some pieces of this rock, which were quite free from the saline effervescence, and infused them in common spring-water for some hours, this water did thereby acquire the true taste of the Hartfell-Spaw. It likewise in the same manner received a deep blue tincture with galls, and contained all the other qualities of that mineral water, without the least difference, that I could observe: which, I think, ascertains the true origin of this mineral spring in the most obvious and undeniable manner.

I am persuaded, that this plain and easy method of investigating the origin of mineral springs is not only superior to the most learned discussions and elaborate theories, but will be found to be the surest, yea, the only way of extending and compleating our knowlege concerning them. As I have not yet had the opportunity of making the experiments, which I designed, upon the two fossils, that we find to be the cause of the above mineral waters, and which will be necessary to elucidate and compleat these observations, which we have made concerning their origin; I shall now only add one thing, and recommend it to the observation of others: “Whether or not, from such a knowlege of the origin of mineral waters, we may not acquire artificial ones of as great, or perhaps of greater, medicinal use, than those, which are naturally produced?”

XVIII. An Account of the State of the Thermometer at the Hague on the 9th of January 1757. Extracted from a Letter of Mr. Abraham Trembley, F.R.S to Tho. Birch, D.D. Secret. R.S.

Hague, Febr. 15. 1757.

Read Mar. 3, 1757.

I Carefully observed the thermometer during the cold days, which we have had this winter. I made use of the same thermometer, with which I made my observations in 1740, and for that purpose fixed it in the same place, where it was that year, viz. in a window directly exposed to the north, and open to a large square. In 1740 I saw Fahrenheit's thermometer at two degrees below 0. This year, on the 9th day of January in the morning, it was at three degrees above 0; that is, only five degrees higher than in 1740.

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XIX. Experimental Examination of Platina. By William Lewis, M.B. F.R.S.

PAPER V.

Read Mar. 17, 1757.

THE account of this extraordinary mineral, formerly read to this illustrious Society, and honoured with their approbation, being since published in the Philosophical Transactions, renders any recapitulation of the discoveries hitherto made unnecessary.

The near and remarkable relation betwixt platina and gold, not only in point of gravity, but in many less obvious properties, hitherto supposed to belong to gold alone; and their as manifest disagreement in others, particularly colour, ductility, and fusibility; induced me to examine, what effects they might have in combination with one another in different proportions; and whether there is reason to credit the report of great frauds having been committed by mixing them together; how far such abuses are practicable; and, what is of more importance, the means by which they are discoverable.

Experiments of the Mixture of Platina and Gold.

Experiment I.

1. Twelve carats[56] of fine gold, and the same quantity of the purer grains of platina, were urged in a blast-furnace, for near an hour, with a fire so strong, that a slip of Windsor brick, with which the crucible was covered, tho' defended by a thin coating of pure white clay, had begun to melt. Upon breaking the vessel, the metal was found in one smooth lump or bead; which, after being nealed by the flame of a lamp, and boiled in alum-water, appeared, both in the mass, and upon the touchstone, of a pale bell-metal colour, without any resemblance to gold. It bore several strokes, and stretched considerably under the hammer, before it begun to crack about the edges. On viewing the fracture with a magnifying glass, the gold and platina appeared unequally mixed; and several small particles of the latter were seen distinct: nor was the mixture intirely uniform after it had again and again been returned to the fire, and suffered many hours of strong fusion.

2. Eighteen carats of gold and six of platina (= 3:1) were melted together as the foregoing, in an intense fire continued about an hour. The bead, nealed and boiled, was less pale-coloured than the former, but had nothing of the colour of gold. It forged tolerably well, like coarse gold. To the naked eye it appeared uniform; but a good magnifier discovered in this, as well as in the other, some inequality of mixture, not withstanding the fusion was two or three times repeated, with the strongest degrees of heat we were capable of exciting by large bellows.

3. Twenty carats of gold and four of platina (= 5:1) were kept in strong fusion for above an hour and a half. These united into an equal mass, in which no granule of platina, or dissimilarity of parts, could be distinguished. The colour was still so dull and pale, that the compound could scarcely be judged by the eye to contain any gold. It hammered well into a pretty thin plate; but we could not draw it into wire of any considerable fineness.

4. Twenty-two carats of gold were melted in the same manner with two of platina (= 11:1) the same that standard gold contains of alloy. The mixture was uniform, of a tolerable golden colour, but easily distinguishable from that of standard gold by a dingy bell-metal cast. It worked well, was forged into a thin plate without cracking, and drawn into moderately fine wire.

5. Twenty-two carats and a half of gold, and one and a half of platina (= 15:1), melted into an uniform mass, which, after the usual nealing and boiling, proved somewhat tougher than the preceding, and of a better colour.

6. Twenty-three carats of gold were melted with one of platina; which is nearly half the proportion, that standard gold contains of alloy. The compound worked extremely well, but was distinguishable from gold by a manifest dinginess, which it retained after repeated forgings, fusions, nealings, and boilings.

7. Twenty-three carats and one-fourth of gold, and three-fourths of a carat of platina (= 31:1), formed an equal mixture, very malleable, ductile like the three foregoing whilst hot as well as cold, but not intirely free from their peculiar dingy colour.

8. A mixture of twenty-three carats and a half of gold, with half a carat of platina (= 47:1), was very soft and flexible, of a good colour, without any thing of the disagreeable cast, by which all the foregoing compositions were readily distinguishable, in the mass as well as on the touchstone, from fine or standard gold.

9. A mixture of twenty-three carats and three-fourths of gold, with one-fourth of a carat of platina (= 95:1), could not be distinguished by the eye or hammer from the fine gold itself.

In all these processes, even where the proportion of platina was small, the fusion was performed by a vehement fire, that the mineral might be the more intimately dissolved, and equally diffused thro' the gold. The necessity of this precaution appeared from an experiment formerly related; in which one of platina having been melted with four of gold, the button appeared not much paler than standard gold with silver alloy. On a second fusion it lost its yellow colour, which had at first been only external, from an imperfect mixture, great part of the platina being concealed in the internal part of the mass, and covered as it were by a golden coat.

The crucibles were rubbed on the inside with chalk, to prevent any particles of the metal from lodging in their cavities. A little borax was employed in each as a flux; with the addition of nitre, by which the colour of gold is somewhat heightened. On remelting some of the mixtures with sundry other additions, powdered charcoal seemed to improve the colour most.

Experiment II.

The preceding compositions, after being gently hammered and boiled, were weighed hydrostatically with great care, by a very tender balance, in distilled water, wherein the gravity of standard gold turned out 17.788.

All the mixtures proved heavier than standard gold. Their gravities were nearer to the medium of the gravities of the ingredients, than those of the compositions of platina with any of the other metals formerly given an account of; none falling considerably short of the mean gravity, and some rather exceeding it.

		Gravity.
		By Experiment.	By Calculation.	Difference.
Platina		17.000
Platina 1	Gold 1	18.140	18.142	0. 02		} Diminution.
Platina 1	Gold 3	18.613	18.714	0.101
Platina 1	Gold 5	18.812	18.904	0.092
Platina 1	Gold 11	18.835	19.094	0.259
Platina 1	Gold 15	18.918	19.142	0.224
Platina 1	Gold 23	19.089	19.189	0.100
Platina 1	Gold 31	19.128	19.213	0.085
Platina 1	Gold 47	19.262	19.237	0.025		} Increase.
Platina 1	Gold 95	19.273	19.261	0.012
Gold		19.285

Experiment III.

As a mixture of platina with an equal quantity of gold has been reported to be specifically heavier than gold itself, but turned out otherwise in the above experiments; some further trials were made on that head.

1. Instead of the crude mineral, whose gravity is but 17, we took platina, that had been cupelled with lead, one of the neatest of the buttons formerly mentioned, which, tho' retaining a portion of the lead, was nearly as ponderous as fine gold, viz. 19.240. This was melted with equal its weight of the gold, in a strong fire, and continued in fusion for about an hour: the mass proved spongy, and very light. We remelted it several times with vehement degrees of fire, suffering it to cool leisurely in the crucible, and, in order to separate as much as possible of the lead, to which its sponginess seemed owing, boiled it in aqua-fortis, and repeatedly injected corrosive sublimate upon it during fusion: the mass, nevertheless, still turned out cavernulous and brittle, and specifically lighter than either the gold or platina by themselves.

2. I likewise endeavoured to combine platina with small proportions of gold. By vehemence of fire, it was made to unite, tho' not perfectly, with half its weight and less: but the mixtures were extremely spongy and brittle; in specific gravity one scarce 16, another less than 15.

3. As a cast metalline body from the Spanish West Indies, of which some account will be given hereafter, appears to have been confounded with the mineral platina, this also was melted with an equal quantity of gold. They united with great ease, by a moderate fire, into an uniform compound, tolerably compact, but whose specific gravity was only 16½; which is nearly the mean gravity of the two ingredients.

Experiment IV.

As a small portion of copper somewhat heightens the colour of pale gold, platina was melted with eight times its weight of standard gold made with copper alloy. The fusion was performed, as in the preceding experiments, in a close crucible, with a strong fire, but without any flux, and continued for about an hour. The metal appeared covered with a black scurf, and had lost about ⅟200. It was much duller coloured, harder to the hammer, and cracked sooner about the edges, than mixtures of fine gold with a larger quantity of platina. By repeated fusion, and frequent nealing, it became a little softer and tougher, so as to be drawn into pretty fine wire; but the colour was still exceeding dull, more resembling that of bad copper than of gold.

The specific gravity of this compound was 17.915; a little less than the medium of the three ingredients unmixed, and a little greater than the mean gravity resulting from the platina by itself, and the copper and gold mixed; for copper, in the standard proportion, appears to diminish the gravity of gold more than it ought to do according to calculation.

From the foregoing experiments it appears, that platina is miscible with gold, in certain proportions, without injuring either its colour or ductility, or occasioning any considerable alteration in the gravity: experiments related in former papers have shewn, that it stands aqua-fortis, and the other trials by which the purity of gold is estimated. It is to be hoped, that the abuses manifestly practicable by this mineral have hitherto been but rarely made use of. To guard against them is the object of this paper; to detect them, of the next.

XX. Experimental Examination of Platina. By William Lewis, M.B. F.R.S.

PAPER VI.
Experiments of distinguishing and purifying Gold mixed with Platina.

1. By Amalgamation with Mercury.

Read Mar. 31, 1757.

IN an experiment related in the fourth paper, an amalgam of one part of platina and two of gold with a suitable quantity of mercury, having been triturated with water for a considerable time, and occasionally washed over, the platina was gradually thrown out, and the gold retained by the quicksilver.

Repetitions of this experiment have shewn, that tho' the separation succeeds in some cases, it does not perfectly in all: that if there is any particle of the platina imperfectly dissolved in the gold (which will generally be the case, unless the quantity of gold is three or four times greater than that of the platina), this part will be retained, after long trituration, undissolved by the mercury, uncomminuted by the pestle, and too ponderous to be washed off in its gross form. A variety of mixtures of platina and gold were treated in the manner above described; and the gold, recovered from the amalgams, submitted to further examinations. Where the proportion of platina was large, the microscope almost always discovered still some granules of it on the fracture of the ingot: where the proportion was small, the recovered gold was frequently, but not constantly, found to be pure.

From these experiments it appears, that mercury has a greater affinity with gold than platina, and that platina is capable of being totally separated by elutriation; but that the process is too vague and undetermined to be applicable in the way of assay, as we have no mark of the precise time for discontinuing it, and as we can never be certain, without making another assay, whether the whole of the platina is separated or not. As a preparatory examination, where the quantities of platina and gold to be separated are large, it is nevertheless of good use, as greatest part of the platina may by this means be washed over with little trouble, and the gold brought into a less compass, so as to be commodiously submitted to a perfect purification by the means hereafter pointed out. This process has a similar effect on platina and gold to that of stamping and washing on metallic ores; which could not be reduced into pure metal in the furnace to advantage, without the previous separation of great part of the earthy and stony matter by water.

2. By Precipitation with Alkalies.

Gold is precipitated totally by fixed alkaline salts, but platina only in part. When solutions of the two metals are mixed together, so much of the platina remains suspended, after saturation with the alkali, as to be readily distinguishable by the yellow colour, which it communicates to the liquor. It has been objected, that tho' the platina was discoverable, when thus mingled superficially with the gold, it may nevertheless, when combined more intimately by fusion, elude this method of trial.

1. Mixtures of gold with small proportions of platina were therefore kept in fusion, by a very strong fire, for several hours, and afterwards dissolved in aqua-regis. The solutions being diluted with water, and a pure fixed alkaline salt gradually added, so long as any effervescence of precipitation ensued, the liquors remained manifestly coloured, tho' apparently paler than when the two metals had been dissolved by themselves.

2. A more convincing proof, that part of the platina remains suspended, after the precipitation of the gold, was obtained, by putting into the filtered liquors some plates of pure tin, which presently contracted an olive hue, and threw down a large quantity of a brownish precipitate, as from the common solutions of the crude mineral. It was observable, that the tin plates were often sensibly acted on, even whilst the liquor was overcharged with alkali.

3. It has been further suggested, and with great appearance of probability, that as a part of platina is precipitated as well as gold by alkaline salts, if only this part be mixed with gold, it will be thrown down by them again upon dissolving the compound. To determine this point, a precipitate of platina made by fixed alkali was melted with thrice its weight of fine gold, and kept in strong fusion for above an hour: they united more easily than gold does with so large a proportion of the crude mineral, and formed a smooth neat bead, which hammered well into a pretty thin plate before it cracked, and appeared internally uniform and equal. This compound being dissolved in aqua-regia, and a fixed alkaline salt added by degrees till the acid was more than saturated, the liquor became indeed pale; but tin plates put into it quickly discovered, that it held a very considerable quantity of platina. It appears therefore a constant property of this mineral to remain partially dissolved in the neutralised liquor; and that minute proportions of it, mixed with gold, are by this means distinguishable.

4. Many other experiments were made of the precipitations and precipitates of gold and platina, by alkalies both of the fixed and volatile kind. The most remarkable effects were, that volatile alkalies, added to both solutions in quantity just sufficient to saturate the acid, precipitated gold intirely, but platina only in part, so much of it remaining suspended as to give the same colour to the liquor as when fixed alkalies were made use of: that, on adding a larger quantity of the spirit after the precipitation of the gold, the liquor became yellow, a part of the metal being taken up again; and that the platina was more copiously redissolved, the liquor becoming of a deep brownish red: that the washed precipitates of both metals, whether made by volatile or fixed alkalies, proved soluble, by moderate digestion, in spirit of salt; those of platina much more difficultly and sparingly than those of gold.

3. By inflammable Liquors.

1. Inflammable spirits, which revive gold from its solutions in form of yellow films, have no such effect on solutions of platina. This experiment affords not only a criterion for distinguishing with certainty whether gold has been debased by platina, but likewise an infallible means of recovering it perfectly pure from any admixture of that mineral. If the compound be dissolved in aqua-regis, the solution mingled with twice its quantity or more of the spirit, and the mixture suffered to stand for some days in a glass slightly covered; the whole of the gold arises to the surface, leaving the whole of the platina dissolved. The golden pellicles may be collected, by pouring the matter into a filter just large enough to contain it. The dissolved platina passes thro', leaving the gold upon the paper, which is to be washed with fresh parcels of water till the liquor runs colourless. The paper is then to be carefully squeezed together, and burnt in a crucible previously lined with vitrefied borax: when fully sunk down, a little fresh borax is to be injected, and the fire raised to melt the gold. The use of lining the crucible with borax is to prevent any moleculæ of the gold from lodging in its cavities.—This process is attended with one inconvenience, the slowness of the separation of the gold from the solution: this may be in some measure expedited by employing a spirit, which has been distilled from vegetables, that give over an essential oil.

2. As essential oils take up gold from aqua-regis, and keep it dissolved for a time upon the surface of the acid; a pure colourless oil, that of rosemary, was poured into about half its quantity of a solution of platina, the mixture well shaken, and suffered to rest: the oil quickly arose, without taking up any thing from the platina, or receiving any colour: the acid liquor underneath remained coloured as at first. Compositions of platina and gold being dissolved in aqua-regis, and treated in the same manner, the whole of the gold was imbibed by the oil, and the whole of the platina remained dissolved in the acid. The oil, loaded with the gold, appeared of a fine yellow colour, and, on standing for a few hours, threw off great part of its contents, in bright yellow films, to the sides of the glass. Sundry other distilled oils were made trial of, with the same event. The gold is easily recovered, by setting the oil on fire; and, when thoroughly burnt out, melting the residuum with borax, as in the preceding experiment. After the separation of the oil employed at first, it may be proper, for the greater security, to add a little more; which, if any part of the gold should happen to have been left in the liquor, will effectually take it up.

3. The experiment was repeated likewise with the subtile fluid, prepared from vinous spirits with the vitriolic acid, called by the chemists æther. The separation succeeded in the same manner as before; the æther receiving nothing from pure platina, but instantly taking up the gold from a mixture of the two. It is observable, that the gold imbibed by this fluid is kept permanently dissolved by it; without separating or reviving, as it does from the common essential oils and vinous spirits.

4. The liquors remaining in these experiments, after the extraction of the gold, appear on all trials the same with the common solutions of platina; and readily betray their being impregnated with that mineral by their colour, by the precipitation with tin, by their yielding a sparkling red precipitate with volatile spirits, &c. A far more minute proportion of platina, mixed with gold, is more distinguishable by these processes, than by those with alkaline salts above-mentioned; these exhibiting the whole of the platina dissolved by itself, those only a part of it.

4. By metallic Solutions.

All the metals, which precipitate gold from aqua-regia, have been already shewn to precipitate platina also. As gold is thrown down by some metallic solutions, as well as by the metals in substance, particularly those of mercury and iron, it remains to apply these liquors as precipitants for platina.

1. A saturated solution of mercury in aqua-fortis, which readily and totally threw down gold in its metallic form, being added to a solution of platina, the liquor became immediately turbid, and, on standing for a little time, nearly the whole of the platina fell to the bottom. A solution of mercury in the marine acid, or of corrosive sublimate, likewise precipitated platina, but less perfectly, and with this difference, that the former precipitate was of a greyish brown colour, the latter of a sparkling red.

2. Solutions of iron in the vitriolic acid, or of common green vitriol in water, which totally throw down gold, happily made no change in solutions of platina. Compositions of platina and gold being dissolved in aqua-regis, the solutions diluted with about twice their quantity of water, and a filtered solution of the vitriol gradually added; the mixtures instantly grew turbid, and, on standing, deposited the gold in form of a purplish grey calx, the whole of the platina remaining dissolved. It appeared, on numerous repetitions of this experiment, that no part of the platina was precipitated along with the gold, nor any of the gold kept suspended with the platina. Where the quantity of the mixt to be assayed was very small, the precipitation was usually performed in a filter, that the gold, which separates in very minute moleculæ, some of which might possibly remain unobserved in the bottom of a glass, might be detained on the paper. The colourless sorts of filtering-paper are preferable for this use to the coloured; as these last may be impregnated with astringent matter, which would extricate some of the ferrugineous part of the vitriol. The vitriol was dissolved in about six times its quantity of water, and a few drops of oil of vitriol added, to prevent the separation of any of its iron in the filter. This solution was put into the filter first, the solution of gold and platina immediately poured into it, the whole stirred together with a clean glass rod, and such part of the liquor, as had run thro' before they had been duly mixed, poured back to the rest. The gold remaining in the filter was washed with fresh parcels of water, the paper cautiously rolled up, and burnt in a crucible, as mentioned in a former experiment.

3. Solutions of the vitriol, recommended by Kunckel and others for precipitating gold of an uncommonly high colour, made no change in the solutions either of gold or platina. The bluish green did indeed precipitate the gold; not as blue vitriols, but by virtue of the ferrugineous matter, of which these kinds largely participate. White vitriol was likewise made trial of, but without producing any sensible effect in either solution.

4. The experiments with green vitriol were repeated on the solutions of platina and gold made in spirit of salt. The event was the same as with those made in aqua-regis; the gold being constantly precipitated, and the platina remaining dissolved.

Remarks.

It may be proper to observe, that by the processes here pointed out, the gold is purified from other metallic admixtures at the same time that it is separated from platina; the inflammable spirits reviving, essential oils and æther imbibing, and green vitriol precipitating, gold alone. Care should be had, that the piece of the mixt, taken for examination, be totally dissolved before any trials are made with the solution; the menstruum not acting with equal facility on the two metals, but dissolving the gold more readily than the platina. Where the acid has been dilute, and only a gentle heat applied, great part of the gold has appeared to be taken up before the platina was considerably acted on. Where the filter, with the gold in it, is burnt in the crucible, borax is the most commodious flux: but as this salt gives a sensible paleness to gold, a little nitre may be injected, after the metal has come into fusion, to restore its colour. If the nitre was added at first, whilst the gold continues subtilely divided, some particles of the metal would be dissipated during the deflagration, which that salt produces with the coaly remains of the paper.

As the foregoing experiments exhibit platina and gold dissolved in a mineral fluid, which by simple mechanic agitation rejects the one and retains the other, and which discovers this different appetite of union so much the more remarkably, as the two metals have been the more intimately combined:—as they further exhibit platina dissolved in liquors incapable of holding gold suspended,—gold dissolved in liquors incapable of holding platina suspended,—gold totally precipitated by substances, which precipitate no particle of platina,—and gold, when mixed per minima with platina, perfectly recovered from it by these means, without increase as well as without diminution:—it follows, that platina is not, as some believe, gold naturally debased by the admixture of some other metallic body, but a metal of a peculiar kind, essentially different from all the others. Before the discriminating characters of platina were discovered, such a notion was highly plausible, and direct experiment seemed to confirm it: a portion of the platina might be separated in the process; a quantity of gold mixed with the remainder, in order to collect the gold supposed to be contained in it; the mixture submitted to operations, which gold alone was supposed capable of withstanding; and the augmentation, which the noble metal still retained, held to be true gold gained from the platina.

The methods of trial above related will, it is presumed, be sufficient to undeceive those, who may have been imposed upon by such appearances, and betrayed into the practice of unintended frauds: to convince them, that all they have gained from platina, after the most laborious attempts to divest it of its imaginary coat, is no other than platina still: and, which is of more extensive utility, to distinguish all the abuses, that may be made with this metal, and restore the gold, so debased, to its original purity and value.

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XXI. An Account of the Temple of Serapis at Pozzuoli in the Kingdom of Naples: In a Letter to John Ward, LL.D. and R.S. Vice-Præs. by the Rev. John Nixon, M.A. F.R.S.

SIR,

Read Mar. 17. 1757.

BEFORE we enter upon a more particular consideration of this noble piece of antiquity, it may not be improper to premise the general account (and indeed the only one I have met with yet published), which is given of it by Mess. Cochin and Bellicard, in a little[57] treatise printed at Paris in 1755. These gentlemen acquaint us, that in 1749 there were only three pillars of this building visible, and that they were buried half way within the ground: but that soon after, workmen being employed by order of the King of the Two Sicilies to dig at the place, they came to the pedestals of those pillars: and at length discovered the building to have been a temple, which (as it was judged by the principal[58] idol found there, and some other circumstances) was dedicated to Serapis. They tell us further, that many statues and vases of excellent workmanship had been taken out of the ruins; and that the whole temple was extremely magnificent, being built, or cased throughout, with marble, even to the parts appropriated to the meanest offices.

This account, tho' short, is yet sufficient to excite in the curious a desire to be more fully informed, both as to the ancient and modern state of this place. To gratify in some measure that desire is the purpose of the present letter.

In order to form any conjecture concerning the antiquity of the building before us, we must know, that the worship of Serapis, to whom it is supposed to have been consecrated, was not introduced at Rome till towards the end of the republic; and then tolerated in the suburbs only[59]. However, at length he was allowed to have temples erected to him within the precincts of the city; chiefly by the authority of Vespasian, who was thought to have restored a blind man[60] to his sight at Alexandria by the aid and direction of this deity. And upon this account he continued to be held in high veneration by Titus and Domitian, the sons of that Emperor, as appears by their [61]stamping his image on the reverse of their coins. Now as it is reasonable to suppose, that the other cities of Italy followed the example of the metropolis in this instance, as we find, they did in others of a similar nature; we may with some probability place the foundation of this temple at Pozzuoli somewhere within the period assigned above.

As for the particular state of this building, it is situated on the west side of the town, near to, and upon a level with, the beach (See [Tab. II.]). Its grand entrance is towards the south, and seems to have been a vestibule supported by four columns. This introduces you into a spacious portico, or corridor[62], which was designed to defend such as assembled here to worship from the injuries of the weather; as also to afford a commodious passage into a range of rooms of different dimensions, disposed on all the four sides of the court.

These chambers seem designed for preparing the sacrifices, lodging the priests, and keeping their vestments; as also the fuel, stores, and other things requisite for the service of the temple: not to omit the convenience of purifying both the priests and the worshippers by bathing or washing. This last destination is countenanced, with regard to the chamber on the north-west and that on the north-east corner, by the row of stone seats, which still remains on each of the sides of the former. These seats have a gutter, or channel running along at the foot of them on the floor; and are likewise perforated with holes of a proper size, with funnels passing from them below. On these benches probably the persons to be purified placed themselves, that the water might be let out upon them from pipes; or administred in vases or ewers by the attendants, and afterwards be carried off by the passages mentioned above[63].

Philos. Trans Vol. L. Tab. II. p. 168.

• A. Ancient grand Entrance.
• B.B.B.B. Portico or Corridor.
• C. Atrium.
• D. Temple properly so call'd.
• E. Altar with it's Drain.
• F. Sacrarium.

• G.G. Two large Chambers for washing &c.
• H. Modern Entrance over Ruins. This seems to have been formerly such a Chamber, as is express'd in the Drawing at (L)

A Scale of Feet.

Nor can a provision for washing or bathing in this temple seem strange to any one, who reflects, how high a rank this mode of purification held among the religious ceremonies of almost all nations of the world. As for the Romans, with whom we are principally concerned in the present inquiry, the subsistence of this usage among them might be abundantly shewn by the testimonies of their writers; and also by the accommodations provided for it in other buildings of the same character with that before us. Some of these still remain within the neighbourhood of Pozzuolo, viz. the magnificent temple near the lake of Avernus ascribed to Apollo, which has an apartment adjoining to it indisputably intended for the purpose intimated above. For it is furnished with several stone cisterns, whose inward dimensions are proportioned to the ordinary size of an human body; and near them is a spring, out of which the water was taken up, and poured into a bason hollowed out in the side of the wall: from thence it ran along in a groove or channel cut in the ends of the cisterns, to be let out upon the persons bathing in them, according to their pleasure, or as occasion should require. So likewise in the temple of Venus (as it is commonly called) near Baiæ, there is a large chamber containing several stone seats for washing, with little cells contiguous to it for undressing before, and anointing the body and dressing afterwards.

I have but one more particular to add concerning the apartment in the north-west angle of the temple, viz. that, when it was cleared of its rubbish, there was found in a niche in one of its sides a male and female figure naked, and in the most flagrant act of natural lewdness. It is now (as we were informed) in a private room in the palace at Portici, nor can be seen without the King's special permission. In the same place, probably, may stand the statue of a satyr in an unnatural action with a goat, which was found at Herculaneum, and is, they say, of exquisite sculpture, but concealed in the palace above-mentioned with the same strict care as the former.

Having thus viewed the several chambers in the exterior parts of the building, it is requisite (in order to a regular prosecution of our design) to return to the grand entrance. And here, passing thro' the corridor above described, we come to a square court or atrium paved with large slabs of white marble streaked with blue or greyish veins. At the distance of 25 feet further, in the center of the said court, stood the temple properly so called, containing a circular area of 54 feet diameter, and elevated above the level of the pavement, so as to admit an ascent to it of five steps[64], in four different parts answering to the four sides of the corridor. This area is surrounded with sixteen pedestals, on which formerly were columns to support a rotundo or dome. Against each of these columns, on the outside, there seems to have been placed a statue, and, in the intermediate spaces, vases for incense, or lavers for washing, upon low stands on the floor. In the middle of the temple was erected the grand altar, the traces of which still remain, with a sink or drain near it to receive and carry off the blood of the victims, &c.

Northward of the temple, and at the distance of 25 feet, being the same space, that was between it and the corridor at the entrance, was once another stately vestibule or pavilion, supported by four columns four feet and an half in diameter, and of the Corinthian order, as appears by three of them, which still subsist standing in a line with the outer face of the corridor. This pavilion (if we may judge by analogy from what we find in other temples) led to an inner recess or sacrarium terminating, probably, in the segment of a circle: but of this we had no certain proof, as the rubbish was not yet removed from this part of the building.

I beg leave further to mention a remarkable appearance in some of the columns of this temple, viz. that that part of them, which was lowermost, as well as that, which was nearest the capitals, is well preserved and pretty entire; while part of the intermediate space for two or three feet together is discoloured, as if it had suffered by burning; and also excavated in such a manner[65], as to contain multitudes of little shell-fish, which appear, like the pholades in some stones, almost totally inclosed within their cells, so as not to be got out without breaking. I know no way to account for this so probable; as by supposing, that the lower parts of these columns were secured by the mass of rubbish, that inclosed them, as the uppermost were by their elevated situation, from being perforated either by the corrosive quality of the sea, which (according to tradition) formerly covered the site of this temple; or by the animalcula, which are bred in that element; while the middle parts standing in the water were (perhaps for ages) exposed to the injuries mentioned above. I had no opportunity of taking the height of the uppermost line, where the above-mentioned alteration in the columns ended, from the level of the sea in the bay; which would have shewn how high the water must have risen formerly above its present mark, to produce the effect ascribed to it on this hypothesis. But, however that may be, the nature of the situation of this place[66] being considered, the innovation supposed to have happened in it will not, I presume, be thought improbable; especially in a country so plentifully stored with combustible matter in its interior parts, and consequently so liable to changes in its outward form, as this is, and has been for many ages. For an extraordinary instance of this we need go but a little way from this place, viz. to Il Monte Nuovo, a hill about four miles in compass, which in 1538 was cast up in one night's time by an eruption, whereby the greatest part of the Lucrine lake was filled up, and the town of Tripergola, with a church, convent, hospital, and other buildings, intirely buried.

I shall conclude with acquainting you, that at the corner of the court of this temple, near the present entrance, there lie some large bases of marble, which (as we were informed) were taken out of the sea at about a mile's distance from Pozzuolo, and are inscribed DVSARI SACRUM. What was the original situation of these monuments, it may not be possible now to ascertain. As for DVSARES mentioned in the inscription upon them, G. Vossius[67] (upon the authority of Tertullian, and Stephanus Byzantius) makes him to have been an Arabian deity, the same as Bacchus or Sol according to the Roman theology. That learned man is likewise inclined to think, that the name DVSARES is compounded of two Hebrew words; one of which signifies joy, and the other, the earth, i. e. mortals, who inhabit it. This etymology properly expresses the genial effects of the sun, which makes glad the heart of man by ripening the fruits of the earth, especially the grape: Whence Virgil calls wine,

Munera lætitiamque Dei. Æn. i. v. 640.

and stiles Bacchus the fabled inventer of it,

——Bacchus lætitiæ dator. Ib. v. 738.

I am,
SIR,
With the greatest respect,
Your most obedient humble Servant,
J. Nixon.

London, March 14. 1757.

XXII. Some Remarks on a Parthian Coin with a Greek and Parthian Legend, never before published. In a Letter from the Rev. John Swinton, M.A. of Christ-Church, Oxon. F.R.S. to the Rev. Thomas Birch, D.D. Secret. R. S.

Reverend Sir,

Read Mar. 24, 1757.

AS we know little of the reigns of the latter Parthian kings, and less still of their coins; an attempt to strike out even the least new light on either of those heads will not, I persuade myself, prove unacceptable to the Royal Society. In this persuasion, I do myself the honour to send you a few conjectures upon another brass Parthian medal, in my possession, as remarkable, on account of the double legend it contains, as the former, which I endeavoured a little to illustrate about a year ago. This medal, which certainly merits the attention of the curious, is in very good conservation, and approaches near the size of those of the middle Roman brass. It exhibits the head, or effigies, of a Parthian king, with a beard, diadem, and hair formed into such curls as I never yet observed upon any antient coins. Under the effigies, the Greek letters ΒΑϹΙΛΕωΝ ΜΕΓΑϹ ΜΟ⦙⦙⦙, which demonstrate the piece to be Parthian, appear; and, on the reverse, a Victory, done something after the Roman manner, tho' the workmanship is pretty rude, presents itself to our view, together with a legend in a language and character at this time unknown. The legend consists of ten complete elements, placed behind the Victory above-mentioned; besides which there is one in the field of the medal, being probably the initial letter of the name of the city where the coin was struck. The metal, tho' termed by me brass, discovers something of a composition similar to that of his Grace the Duke of Devonshire's medal of Vologeses III. as described by [68]Sig. Haym. This coin, of which I herewith transmit you a draught most accurately taken (See [Tab. IV.] Fig. 1.), having not yet, as I apprehend, been published; you will permit me now to offer a few cursory remarks upon it, drawn up in the shortest and most concise manner possible.

1. The Greek legend, had all of it appeared, would, undoubtedly have been either ΒΑϹΙΛΕωΝ ΜΕΓΑϹ ΜΟΝΝΗϹΗϹ, or ΒΑϹΙΛΕΥϹ ΒΑϹΙΛΕωΝ ΜΕΓΑϹ ΜΟΝΝΗϹΗϹ; of which I should chuse the former, notwithstanding it is such Parthian Greek, as the round of the medal seems not to have been capable of containing the latter. It will be, at first sight, observed, that this legend is different from those of the Parthian coins hitherto described; which are exhibited in the [69]genitive, not the nominative, case. The last two letters MO leave no room to doubt, tho' the O is not so extremely well preserved, that the piece was struck when Monneses sat upon the Parthian throne. It is true, indeed, the first element of the prince's name is not so apparently a Mu; tho' it resembles that letter, even as preserved on this very medal, much more than any other of the Greek alphabet. It is however totally unlike the Alpha near it, as well as all the other forms of that element to be met with in Montfaucon[70], and bears not the least resemblance to Beta[71], particularly the Beta which ought to have been impressed on this piece; as most evidently appears from a particle of that letter, visible in its proper place. From whence we may infer, that the character I am considering must be Mu; as Alpha, Beta, and Mu, were the only initial letters, according to Dr. Vaillant[72], of the names of the Parthian kings reigning after the introduction of the Omega of the minuscular form, as it here occurs, upon the Parthian coins. But Monneses was the only one of those princes whose name began with My, and consequently the two last Greek elements on this medal are part of his name. The metal and size of this piece, as none belonging to the other Parthian monarchs seem to have been yet met with of the same form, which exactly agree with those of Monneses's[73] coin published by Dr. Vaillant, may likewise be urged, as an additional argument of no small weight, in support of my opinion.

Philos. Trans. Vol. L. Tab. IV. p. 176.

Fig. 1.

Num. Parth. apud Jeannem Swinton, A. M. Oxoniens. R. S. S.

Fig. 2. p. 202.

Scale of feet, 20-1 Inch

J. Mynde sc.

2. That the Greek and unknown legends on this medal are either of the same or a similar import, will be acknowleged by all versed in this kind of literature extremely probable. The Greek and Phœnician legends on the same [74]coins of Tyre and Sidon, as I have, upon examination, found, and shall hereafter more fully evince, clearly correspond. The Latin and Punic legends on Juba's medals, as has been by me formerly proved[75], very well agree. The sense[76] I have assigned the legend in unknown characters, exhibited by the reverse of my former Parthian coin, with, I flatter myself, some appearance of truth, sufficiently answers to the Greek one preserved by other medals of the same prince. We may therefore be permitted to suppose, that both the legends handed down to us by the coin before me related to Monneses, and conveyed the same, or at least extremely similar, ideas to the Parthians and the Greeks. Nothing can be more consonant to reason, tho' we must not directly assume this as a postulate, than such a supposition.

3. This notion will likewise receive a farther accession of strength from the characters of which the unknown legend is composed. The first of them so nearly approaches one of the forms of the Palmyrene Pe, as it appears in [77]Mr. Dawkins's alphabet, that we may without scruple ascribe to it the power of that letter. The second is so like the Palmyrene and the Chaldee Daleth[78], that it ought indubitably to pass for that element. The third differs something, tho' not greatly[79], from one of the forms of the Palmyrene He. The fifth, which likewise occupies the eighth place, is by no means remote from the figures of the [80]Palmyrene and Chaldee Nun. The sixth occurred in the third place before. With regard to the seventh, it seems to me pretty strongly to resemble some forms of the Palmyrene Mem[81], and even exactly to answer to that of the same letter in [82]one of the Palmyrene inscriptions preserved amongst those celebrated remains of antiquity commonly, tho' perhaps improperly, stiled The Ruins of Persepolis. The ninth is the He touched upon before. The tenth, which also succeeded the third, if the powers of the other elements have been rightly determined, must be Schin. Nor does this character, if we view it in a certain position, appear very remote from a rude form of that letter. This legend then, according to what is here advanced, as it now remains, consists of the words——PADESHANE MONESH, PADESHAN EMONESH, or [83]PADESHAN AMONESH, that is, MONESH, or AMONESH,——OF KINGS; the word PADISHAH, or rather PADESHAH, as it seems to have been written and pronounced by the [84]ancient Persians, in the Pehlawian, Pehelawian, or Bastanian, that is, the old Persic, tongue, denoting [85]King. That NI, or NE, was sometimes a masculine plural termination in the antient Persic, seems to appear from the word, or rather words,

, BIR. ZEIVESHNI, LONGÆVI, which occurs in Dr. Hyde[86]. And that the vowels A and E were sometimes prefixed to the Persian proper names, in the remoter periods of time, is abundantly manifest, from the words SFITAMAN, ESFINTAMAN, or ESPINTAMAN, the [87]name of either the father or one of the ancestors of Zerâtusht; XERXES, [88]AXERXES, or AXERSES, and others of the same kind, that might, with equal facility, be produced. Whether therefore we read this legend——PADESHANE MONESH, PADESHAN EMONESH, or PADESHAN AMONESH, we cannot greatly err. As the coin was not so perfectly struck, part of the Greek legend is thereby apparently lost; from whence, and the evident want of a word there, we may conclude, that the Parthian legend, for Parthian by the explication here laid down it appears to be, on the correspondent part of the reverse, must have met with the same fate. What that Parthian term was, I cannot take upon me to say; but the whole legend was probably something like THE GREAT KING MONNESES, MONNESES THE KING OF KINGS, or MONNESES[89] THE GREAT KING OF KINGS; all which titles are intirely consonant to those assumed by the Parthian kings[90], and transmitted down to us on their other coins. The Persian, or Parthian, termination of the proper name MONNESES, and others that occur, was ESH. This may be inferred from the legend now before me, in conjunction with Scripture[91], and has been remarked by some good authors[92]. That the Greeks also expressed the Schin by their Sigma, and superadded another termination to such words, is sufficiently manifest from the Persian, or Parthian Arshak[93], which was converted into Arsaces by the Greek writers. I must farther observe, that, according to Herodotus[94], the antient letters of the Persians were those used by the Assyrians; which I take to have been the same with the elements that prevailed amongst the Syrians, and formed the alphabet of the Palmyrenes. Nay, we may collect from [95]Epiphanius, that a considerable part of the Persians used the Palmyrene characters as late as the decline of the fourth century after Christ. All which being maturely weighed, I cannot forbear thinking the interpretation of the Parthian legend here laid down in a good degree probable. I am far however from insisting upon the truth of it. I shall only beg to be indulged the liberty of proposing it to the consideration of our most illustrious Society, and leave the fate of it intirely to the decision of so very eminent a part of the learned world.

4. But however my explication of the Parthian legend may be received, I believe it will scarce be denied, that the coin was struck in the reign of Monneses, one of the Parthian kings; this point having been so clearly evinced, by the reasons above alledged. It may not be improper here to remark, that the republic of letters has been obliged with the publication of two of this prince's medals; the first of which was [96]coined in the year of the Parthian æra 422, and the other in 425[97]. Neither of them however exhibits the Victory impressed on the reverse of mine. That symbol, adopted by the Parthians in imitation of the Roman manner, must undoubtedly have alluded to some victory, or at least some remarkable advantage, gained by the Parthian forces over the Romans, a little before the piece was struck. What that advantage was, when and where obtained, and whether history conspires with the medal, in order to settle this point, I am next to inquire.

5. Monneses, if Dr. Vaillant[98] may be credited, ascended the Parthian throne in the year of the Arsacidæ 422, nearly coincident with the 166th of Christ, when M. Aurelius and L. Verus presided over the Roman world. But so far were the Parthians at that time from gaining any victories over the Romans, that they were every where worsted by them, and put to the rout. A Roman army, under the command of Avidius Cassius, had penetrated into Mesopotamia and Assyria, ravaged those provinces, laid Seleucia in ashes, taken Ctesiphon, and levelled the royal palace there with the ground, according to Dio[99], the preceding year. Nay, it appears both from [100]Capitolinus and the Roman[101] coins, that M. Aurelius and L. Verus triumphed over the Parthians, the very year after Monneses, as [102]Dr. Vaillant will have it, came to the crown. All which that celebrated antiquary acknowleges to be true; and adds, that Monneses concluded an infamous peace with the Romans, ceding to them the whole province of Mesopotamia, for which he was soon after deposed by his subjects. Here then we can discover not the faintest traces of a reason for the appearance of a Victory upon the medals of this prince. Nor does any thing like a reason for such an appearance, in antient history, occur, before the 950th year of Rome, corresponding with the 197th of Christ; when the Parthians, animated by the civil dissentions, which reigned amongst the Romans, Albinus and Severus then fiercely contending for the empire, entered Mesopotamia with a powerful army[103], and reduced to their obedience most of the cities of that province. Now if, with F. Corsini[104], we admit the commencement of the Parthian æra to have happened in the 525th year of Rome; the 425th or 426th year of the former and the 950th of the latter of those æra's, wherein the Parthians undertook the Mesopotamian expedition, will nearly coincide. But it may be proved from a medal of Monneses, described by the [105]Marquis Scipio Maffei, in opposition to [106]Dr. Vaillant, that this prince was not dethroned in the year of the Arsacidæ 423, but had two years afterwards the management and direction of the Parthian affairs: wherefore, notwithstanding what has been advanced to the contrary by that antiquary, he might still have sat one or two years longer upon the Parthian throne. This may likewise be inferred from Dio, who mentions Vologeses as presiding over the Parthians, not in 198, but in 199, about two years after their irruption into Mesopotamia. All which being with proper attention considered, it will appear extremely probable, that the medal I have been endeavouring to explain was coined either in the 425th or 426th year of the Parthian æra, that is, the 197th of Christ; that the authority of [107]Arrian, [108]Justin, and [109]Athenæus, on which F. Corsini principally sounds his notion, may be intirely depended upon; and, in fine, that the arguments he makes use of on this occasion, to [110]evince the truth of his scheme, however they may be opposed by F. Frœlich, and the medal before me mutually strengthen and support one another.

6. I must not forget to remark, that F. Corsini thinks, without a proper foundation, that the piece of Monneses published by Dr. Vaillant may be considered either as a Parthian or [111]an Armenian coin. This, I say, he takes, without a proper foundation, to be the case. For the medals of the Armenian kings, such as that he has obliged the learned world with a draught of, and a most excellent dissertation upon, discover a taste far different from that which is exhibited by Dr. Vaillant's coin. The air of the face, the curls into which the hair is formed, and in fine every thing else visible upon the former, except the symbols on the reverses, bear little resemblance to what is presented to our view by the latter. As for the titles, impressed on these medals, they are far from being of the same kind; the Armenian princes in this particular approaching nearer the successors of Seleucus[112], and contenting themselves with more plain and simple titles than that lofty one affected by Monneses, according to Dr. Vaillant, in common with the other Parthian kings. To which I may add, that my coin sets this point beyond dispute, by the Parthian characters it has so apparently preserved; all the Armenian medals I have hitherto met with, about three or four in number, as well as that of Baron Stosch[113], which F. Corsini has so learnedly explained, having only Greek legends upon them. What therefore he has advanced, on this head, must be considered as not altogether so consonant to truth; especially, as he seems to have offered nothing of any great weight in support of his opinion.

7. Before I dismiss the present subject, I must beg leave to take notice of the Parthian character on the field of my medal, which is not very unlike the Chaldee[114] or Palmyrene Aleph, tho' of something a more complex form. Should this be allowed, that character may be considered as the initial letter of ARSACIA, the name of a city subject to the Parthians, placed by [115]Ptolemy in Media; where, according to [116]Dr. Vaillant, many of the Parthian medals were coined. That city is however believed by some to have been seated on the spot occupied at this time by Casbin, or rather Kazwîn[117], one of the principal towns of the Belâd Al Jebâl, or mountainous part of the Persian Irâk; for a particular account of which place, the curious may have recourse to Golius, and the eastern geographers. As I have already far exceeded the limits proposed to myself, when I began this letter, I shall not now touch upon any other observations relative to the medal before me, which is the only one I have hitherto met with carrying a Greek and a Parthian legend upon it; but only assure you that I am, with the most perfect regard,

SIR,
Your most obliged
and most obedient Servant,
John Swinton.

Christ-Church Oxon. Nov 29th, 1756.

---

XXIII. An Account of a Red Coral from the East-Indies, of a very singular Kind: In a letter from Mr. John Ellis, F.R.S. to Mr. Peter Collinson, F.R.S.

Dear Sir,

Read Mar. 24, 1757.

I Promised you, in my letter of the 7th of February 1754, published in our Transactions, Vol. xlviii. p. 507. that I would, when I had an opportunity, endeavour to illustrate the tubular structure of the common red coral of the Mediterranean sea, and of some of the keratophyta; which two kinds, tho' evidently of as different natures as stone and horn, yet are, from late observation, found to be fashioned, or raised up into those beautiful forms, by animals of the same class.

This I shall attempt to do, by comparing them with bodies of a similar kind, but of a less compact texture: for which reason I formerly referred you, in the above-mentioned letter, to a figure, which I have given of the herring-bone-coralline with its animals alive in it, Phil. Trans. Vol. xlviii. Tab. XVII. Fig. E, F, G, to shew you the nature of the tubular structure of the keratophyta.

Philos. Trans. Vol. L. Tab. III. p. 189.

J. Mynde

A. A piece of pithy knobbit and Coral from the Spice Islands in the East Indies which appears to be form'd by animals of the Polype kind, contrary to the receiv'd opinion of these bodies being vegetables; the vermicular tubes, of which it is compos'd, being no more than the cases or coverings of the bodies of these Insects.

B. The radiated holes on the yellow mealy surface, through which these insects extend their arms or claws, as in the common red coral.

CC. Small Branches almost cover'd by a further addition of tubes, that have risen all round and increas'd the bulk of the Stem, continuing themselves along it to extend the ramifications; by this means they involve the former side branches into their own stem, differing intirely from the laws of vegetation.

D. A piece of y^e. knobby joints magnified to shew their reticular texture like that of spongy orange wt^h tubes.

d. The same in its natural size.

E. A piece of y^e. blood red tubes which is harden'd into a shelly or stony substance with some appearance of reticulations, taken from y^e. space between y^e. knobs.

e. The same in its natural size.

F.F. Small holes in y^e. branches of y^e. polypes.

G. A mass of the stem not so highly magnified shewing y^e. tubes passing from stony to spongy.

g. The same in its natural Size.

H. The transverse section of the base shewing the holes in the ends of the tubes.

I. One of the radiated cells magnified, this is guarded by 8 pointed valves, which close inward, when

K. the Polype draws in his head (which is figur'd at K) and opens outward when it extends it.

I now lay before you a piece of red coral (See [Tab. III.] Fig. A.) from the East Indies of a very singular kind, which I received from your friend Abraham Hume, Esq. The stem and branches of this appear evidently to the naked eye to consist of a combination of vermicular tubes closely connected together: and, if we trace these little tubes to their starry openings on the surface, Fig. B. we shall plainly discover them to be the red testaceous coverings of certain marine polypes, which have raised themselves thus upright, and disposed themselves into this remarkable vegetable form.

In order to form some idea, how these masses are increased and extended to the sizes we often meet with them, and where the same regularity of shape is preferred in the large, that we find in the small; we think it more than probable to suppose, that the species of polypes, that compose this coral, breed as we find all other polypes do: and this appears more evident to me, from what I have already discovered in many kinds of corallines (See Plate 38. of my Essay on Corallines), where the young polypes in some species are produced in the egg state, while others fall in great numbers from their matrices, completely formed, down to the roots of their parent corallines, either to begin a new race of the same species near them, or to increase the trunk, and extend the ramifications, of the plant-like figure which they just descended from.

From observing this method in nature, we shall the easier account for the progress of those generations of young testaceous polypes of this coral; which appear to us succeeding each other, and raising themselves up from the root or base, passing along the stem and branches, and covering the whole anew with their shelly cases: and in this their passage upwards we may observe, in the specimen before us, how they have involved and incrusted the small lateral branches of the former generation, so as almost to hide their appearance. From hence we may trace them extending themselves to the extremities of the upper branches, and there forming a new series of slender twigs, proportionable to those which they had just covered, still keeping order and exact symmetry in the whole structure.

The distinguishing character of this red coral, after we have considered its fistulous texture, is the knotty joints, of which it is composed: these appear more distinct, and are placed at a greater distance, in the smaller branches than the large; and, as we descend to the trunk, the traces of these inequalities but just appear.

From these protuberances, or knots, the lateral branches take their rise; and as these and the leading branches grow up together, they frequently inosculate at these joints, forming a kind of network, like what we observe in many of those species of keratophyta, which are called sea-fans.

The surface of this coral, when recent, is covered with a mealy friable matter, of a yellow colour, not unlike that of the true red coral, but much fuller of little raised starry cells. The figure of these cells is owing to the radiated position of the claws of the polypes.

Upon removing this friable matter, we observe, that the polypes of these cells have had a communication with a small hole or opening into one of the tubes, that lie immediately under it.

This frequent intervention of the openings of the small tubes, or their ramifications, between the sides of the larger ones, makes the latter appear more irregular, and not so parallel, as in the true red coral; where we find fewer stars; and, where those occur, we may observe it always alters the direction of the tubes.

I must further remark to you, that many of the tubes of this coral appear, thro' a magnifying glass, full of small holes, like those I have described in the keratophyton (Plate 26. Fig. G. p. 62. of my Essay on Corallines); and these holes will appear more distinctly to you, when you examine the half tubes, or broken irregular ones, on the stem and great branches of this coral.

Further, if you compare the transverse section, at the base of this coral, with a section of a common Rattan cane, they will both appear full of holes in the same regular order, and of nearly the same diameter: whereas the tubes, on the surface of the stem of this coral, look as irregular as so many holes pierced or eaten out by worms.

I hope by this time our ingenious botanical friends, whom we could not persuade to part with these beautiful sea-productions from the vegetable kingdom, are thoroughly convinced, that this mealy, friable, or calcarious covering, full of starry cells, which we are sure to find covering all the recent red corals and keratophyta, is not a mere blight of insects, common to the sea vegetables as well as land ones, which they have formerly insisted on; but that they will consider this covering, for the future, as proper and necessary for the well-being of these little animals, as they do at present hair and wool for beasts, feathers and down for birds, and scales and slime for fishes.

This red coral is mentioned by Rumphius, in his Herbarium Amboinense, Vol. vi. Tab. 85. p. 264, but, as the figure he has given, is not sufficient to demonstrate its tubular texture and animal structure, I have had it more accurately drawn; and those parts in particular magnified, which may tend to illustrate the foregoing description. He mentions, that it is in great esteem with them, on account of its beautiful figure; but would be much more so, if it was not for the great difficulty they find in preserving the smallest twigs from falling off; which is the reason, I suppose, that the specimen is not more complete.

Lastly, he tells us, that it is used by the inhabitants of the Spice-islands as a principal ingredient in their medicines to expel poison: as also, that they have it in great esteem on account of its excellent diuretic quality.

Upon examining this coral in the microscope, I observed, that the outside tubes of the stem were chiefly stony, but that the inward parts were composed of as many divisions of spongy tubes, as there were of stony ones.

This I find arises from the smaller ramifications, which being spongy at the knobs, and stony in the spaces between them, are inclosed and united together into one common mass during the growth of this coral; so that both the soft and hard parts together make up the inside of its trunk or stem. When we examine minutely the two parts, that compose the branches, we find, that the knobs consist of little sponge-like tubes interwoven together, as they appear magnified at Fig. [D]; and the shank or part between the knobs is composed of stony tubes, that are more erect (See the piece magnified at [E]): these tubes appear to be branched from the lateral holes at [FF.] The Fig. [E] likewise shews the appearance of the tubes on the surface of the main stem.

The radiated openings in the little wart-like figures on the surface of the branches are guarded by eight pointed valves, as magnified at Fig. [I.]: these inclose the heads of the polype, one of which is figured at [K.]

The stem of this specimen is so intirely divested of its yellow mealy covering, that we may easily trace the manner in which the animals, that compose it, have carried up their stony tubular cells, which lie side by side along the surface. These tubes have still some marks of sponginess at particular distances, which, as they come to join together, form those irregular cross-lines, that surround the stem in several places. See Fig. [A.]

In other specimens I have observed the principal stems covered over with calcarious tubes, such as I have described in the Essay on Corallines, &c. in that species of keratophyton called Venus's Fan. Plate 26.

The sponginess of the knobby joints occasions that excessive brittleness in the lesser branches; which accounts for the difficulty, which Rumphius mentions, of getting good specimens of this beautiful coral.

I have lately seen a white pipy and stony coral with spongy knobs, which is only a different species of this genus, in the very curious cabinets of our friends Dr. John Fothergill, M. D. and Mr. Isaac Romilly, F.R.S. specimens of which they have both lately received from the East Indies. The examining of these has given me an opportunity to be more particular in the description of this coral; which seems to point out to us the great affinity there is between corals, keratophyta, and sponges.

I am,

Dear Sir,
Your most affectionate humble Servant,
John Ellis.

Laurence Lane, Mar. 24, 1757.

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XXIV. An Account of the Effects of a Storm at Wigton in Cumberland. Communicated by Mr. Philip Miller, F.R.S.

To the Rev. Tho. Birch, D. D. Secr. R. S.

SIR,

Read Mar. 31, 1757.

I Received the inclosed letter by the post, giving an account of the storm, which happened lately in the north. If the Royal Society have not already been informed of the effects of it, and you think the contents of it worthy their notice; I beg you will be so good as to communicate it to them. The facts therein mentioned have been confirmed to me by a person of skill and integrity. Mr. Thomlinson's conjecture of the cause of the leaves of trees appearing scorched after the storm, I believe to be true; having two or three times myself observed the same in Sussex, at a considerable distance from the sea; when all the hedges, trees, and woods, on the side toward the sea, have had their leaves scorched, as if fire had passed over them; and their opposite sides from the sea have continued in full verdure; which frequently happens in storms from the south-west: and, upon tasting their leaves, I have found them as salt, as if they had been steeped in brine. I am,

SIR,
Your most obedient humble Servant,
Philip Miller.

Chelsea, Nov. 23. 1756.

To Mr. Philip Miller.

Wigton, Nov. 15. 1756.

SIR,

ON the 6th of last month, at night, happened a most violent hurricane, such an one, perhaps, as has not been known in these parts in any one's memory. It lasted four hours at least, from about eleven till three. The damage it has done is very deplorable. The corn has sufferd prodigiously. Stacks of hay and corn have been intirely swept away: houses unroofed, and in several places driven down by its fury: trees without number torn up by the roots; others snapt off by the middles, and their fragments scattered over the adjoining fields. Some were twisted almost round, or split down to the very ground; and, in short, left in such a shattered, mangled condition, as scarce any description can give you an adequate idea of.

The change in the face of the country was very surprising in one single night: for, to complete the dismally-desolate scene, the several tribes of vegetables (in all their verdure the day before), as if blasted with æthereal fire, hung down their drooping heads. Every herb, every plant, every flower, had its leaves withered, shrivelled up, and turned black. The leaves upon the trees, especially on the weather side, fared in the same manner. The evergreens alone seem to have escaped. The grass also, in a few days time, recovered itself in a great measure.

I agreed at first with the generality of people in their opinion, that lightning had done all this mischief: but upon recollecting, that there had not been much seen any where, in many places none at all, but that the effect was general[118], as far as ever the wind had reached; I began to think, that some other cause might probably be assigned. Accordingly, I set myself immediately to examining the dew or rain, which had fallen on the grass, windows, &c. in hopes of being enabled, by its taste, to form some better judgment of the sulphureous or nitrous particles (or of whatever other quality they were), with which the air was so strongly impregnated that night, as to produce such strange effects. Nor was I deceived in my expectations: for, upon tasting it, I found it as brackish as any sea-water. The several vegetables also, which I tasted, were all salt, more or less, and continued so for five or six days after; the saline particles not being then washed off; from the corn and windows in particular; the latter of which, when the moisture on the outside was exhaled next day, sparkled and appeared exceeding brilliant in the sunshine. This saltness, I conceive, has done the principal damage: for common salt dissolved in water, I find, upon experiment on some fresh vegetables (when sprinkled two or three times upon them) has the very same effect, except that it does not turn them quite so black: but particles of a sulphureous, or [119]other quality, may have been mixed with it. That this salt water had been brought from the sea[120], every body, I think, will allow; but the manner how[121], is not so easy to conceive.

This freedom, Sir, perhaps may want an apology: but, as a gentleman[122] of the Society you have the honour to be a member of, did not think something of the like nature either unworthy of his own notice, or that of the world; and as the hurricane principally affected these parts of nature, in the knowledge of which you have so eminently distinguished yourself; I flattered myself you would excuse the trouble I should give you in a perusal of an account of this very strange, tho' hitherto unnoticed, phenomenon.

I am, Sir, with the greatest respect and esteem,

Your most humble Servant,
Thomas Thomlinson.

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XXV. An Account of the Effects of Lightning upon the Steeple and Church of Lestwithiel, Cornwall; in a Letter to the Right Honourable the Earl of Macclesfield, President of the R.S. By Mr. John Smeaton, F.R.S.

Read April 21, 1757.

JAnuary 25. 1757. about five o'clock in the evening, returning home from the Edystone works near Plymouth, I observed four flashes of lightning, within the space of six or seven minutes, towards the west; but heard no noise of thunder[123]. A few days after, I was informed, that the same evening the lightning had shattered the church of Lestwithiel in a very surprising manner.

The 1st of March I was at Lestwithiel: they had then begun to repair the damages; but had not made such a such progress, but that the principal effects were equally observable as at first. I observed, and was informed, as follows:

At the time before-mentioned, the inhabitants were alarmed by a violent flash of lightning, accompanied with thunder so sudden, loud, and dreadful, that every one thought the house he was in was falling upon him; almost every one being within doors, on account of a violent shower of rain, which preceded the lightning: so that no body saw or heard any thing of the mischief done to the church, till it was observed accidentally after the shower.

The steeple is carried up, plain and square, to about 49 feet, with a kind of slate-stone, rough-casted on the outside; upon which is formed a very elegant octogon Gothic lanthorn about 9 feet high, and thereon a stone spire about 52 feet height, with a spindle and vane rising about 3 feet above the stone: so that the whole together was about 113 feet. Each face of the lanthorn finishes above with a sort of a Gothic pediment, with a little pinacle upon each, separated from the body of the spire.

I will not affirm, that the lightning entered in at the spindle or vane at top; but will suppose it, for the sake of methodizing the facts. The vane was of plate copper, which being turned round, and rivetted, made a socket to turn upon. The spindle did not reach thro' the socket, but the weight of the vane rested upon the top of the spindle, the top of the socket being closed. About the vane were many acute angles, and some almost sharp; but I did not observe any pointing directly upward. The vane was much bruised, which might be occasioned by the fall; but the socket was rent open, as if it had been burnt by gunpowder; and in such a manner, as I cannot conceive could be occasioned by the fall. Under the spindle, that carried the vane, was a bar of much the same size and length[124], that passed thro' the center of several of the uppermost stones successively, in order to unite them the more firmly together, and was run in with lead: all which surrounding stones were broke off, except one, which, together with the bar, fell down within the tower.

The shell of the spire, as far down as 35 feet from the top, was no more than 7 inches thick, and the courses about the same height: so that scarce any one stone in the spire could weigh more than 30 or 40 pounds; but they were joined together at the ends, with mortoise and tenon, in a curious manner. Above 20 feet of the upper part was intirely thrown down, and dispersed in all directions; and, as I was informed, some pieces were found at the distance of 200 yards. A great many stones fell upon the roof of the church; and several made their way thro' both roof and cieling down into the church, breaking the pews, and whatever they fell upon. Six feet still lower the spire was separated; the westermost half being thrown down; the eastern half was left standing, but disjointed, and in so critical a posture, that it seemed ready to fall every moment: so that this was ordered to be taken down immediately; and likewise to 6 feet below, the work being found remarkably shattered. In this condition it was when I saw it. The whole of the spire I found much cracked and damaged, but the remainder of the 7 inch shell so greatly, that there seemed scarcely a whole joint.

The pediments over every face of the lanthorn were damaged more or less; but the whole ashlering of that to the N.W. was torn off from the inner wall, to which it was connected. At first sight this might seem to be done by the falling of the stones from above; but I was convinced to the contrary, by observing, that several of the pediments were damaged, and even stones struck out, where the little pinacles above them were left standing.

About the top of the lanthorn is a bell for the clock to strike on: it is hung upon a cross-bar, with gudgeons at each end; the whole being suspended to a beam laid across the tower. The cross-bar was so bent, that the clock-hammer would not touch the bell by above 2 inches. This could not be done by the falling of stones, because the beam would defend the bell from receiving any stroke in the direction to which the cross-bar was bent. As to the wire, that drew the hammer, as I was informed, not one bit of it could be found.

The bells (four in number) for ringing hung in the square part of the tower, below the lanthorn, two above and two below: the wheels of every one were broke to pieces, and one of the iron straps, by which they are fastened to the yoke, unhooked; and, as appeared to me, could not be replaced without great force, or unloosing. Whether these accidents were occasioned by the lightning, or the falling stones, I leave undetermined.

In the floor under the bells was placed the clock, cased up with slight boards. The verge, that carries the pallets, was bent downwards, as if a ten pound weight had fallen ten feet high right upon it. The crutch, that lays hold of the pendulum, looked as if it had been cut off by a blunt tool, and heated by the blow, till it was coloured blue, at the place where it was cut. It turned at a right angle, and might be about 4/10 of an inch broad by 2/10 thick. As to the pendulum, which hung pretty near the wall, the upper part of the rod was struck with such violence against the wall, that a smart impression thereof was made in the plaister: and near the upper part of the impression appeared a circular shady ring, of a blackish colour, something like as if a pistol had been discharged of powder, and the muzzle held near the wall. The casing of boards round the clock remained unhurt.

In this story, on the north and south side, are two narrow windows or air-loops; against the upper part of which, on the outside, were fixed the timber dials belonging to the clock, both which were blown off, and broke to pieces, possibly by the fall: and not only that, but part of the stone jambs were broke out also, near to where the rod passed, that carried the hands. In this story also was a sort of window or air-loop on the east side, that had communicated with the church, but was stopped up with lath and plaister: also several putlock-holes for the scaffolding, which had gone thro' the wall into the church, but were stopped up with stone, and plaistered over: all these were forced out into the church, and the plaister torn from the wall.

The ground-story of the tower or bellfrey is expressed in the plan (See [Tab. IV.] Fig. 2.). The south entrance A and north B were shut with wooden doors. The upper part of the eastern C, that communicated with the church, was made up with lath and plaister; and before it, in the church, are the seats D, raised one higher than another; so that the floor of the seats next the wall was half up the door-way; consequently the vacuity under the seats lay open to the bellfrey.

About the middle of the westermost side, at a, one of the paving-stones, about 1 foot square, and 1½ inch thick, was thrown up, and a hole pierced into the wall, rather below the level of the pavement, into which one might put three fingers. On the opposite side, the south-west angle of the middle buttress at b had a stone taken out even with the ground, and a hole continued in to the buttress; so that there is great appearance of its reaching thro' both wall and buttress, which together is 8 feet; but the hole was too rugged and crooked to put any thing thro'. Besides this hole, this wall was pierced in several places, and the plaister thrown off both within and without. One place within, about 4 feet above the floor, right over c, was a hole of about 14 inches square pierced 6 inches in the wall; and so near square, that I inquired, whether it had not been made by art; but was assured of the contrary.

The north and south doors of the tower were both blown out, and broke in many pieces. Many of the arch-stones over both doors were disjointed and displaced: two of the stones making the jamb of the south door at g were forced quite out, and one of them broke.

The vaulting of the east door-way C was plaistered underneath: the plaister was sprung from the stone in 30 or 40 places, like as if a small bar of iron had been drove from above thro' the joints of the stone, and thereby forced off the plaister with its end. The lath and plaister partition, which stopped up the upper part of this door-way, was forced into the church, and the wainscotting making the back of the last seat was torn from the wall from end to end. Some part of the vapour seems to have made its way thro' the cavity under the seats; for most of the boards composing the rise of the steps from seat to seat were blown out forwards; and several panels of wainscot at each end of the seats, at d and e, were forced out, and broke. Hence the vapour seems to have divided itself into three branches; one moving directly forward to the east window G, being 13 feet wide, and about 20 feet high, consisting of five principal lights divided by stone mullions: two of the lights were in a manner wholly destroyed, and several large holes in those remaining; the glass and lead being carried outward, like as if an harlequin had leaped thro' the window. The north window E, fronting the broken panels at d, was very much shattered: but the south window F had scarce a whole pane left.

It is farther to be noted, that almost all the lights in the church, tho' not broke, were bagged outward; but those parts remaining intire in the window D most remarkably so.

N.B. It was said in the London papers, that the organ was intirely spoilt: it is certain there is not, nor ever was, any organ in this church.

XXVI. An Account of the Case of the late Right Honourable Horace Lord Walpole; being a Sequel to his own Account published in the Philosophical Transactions, Vol. xlvii. p. 43. and 472.