version, in 1841, puts it at 510ft. It is difficult to say which of these two doctors, who differ, should be accepted as the more trustworthy; and in 1841 Dr. Granville would still certainly be able to find plenty of persons familiar with the well and its details. But in the ferruginous sand, or near it, the spring was to be expected; and there it would seem Messrs. Isler, in the new boring, found saline water, though only in small quantity. The depth, according to their computation, was, as we have said 490ft., which is 20ft. above the Spa spring’s level, according to Granville’s version, and 60ft. above the depth given by Snaith. The paucity of the supply of the saline water in the Isler boring may probably be accounted for thus: The trend of the current found in making the Spa well was said to be from south-east to north-west, whereas this new bore is very nearly due west from the Spa well. If, therefore, the stream is of narrow width, this later boring is scarcely in the position to catch more than the side soakage of the current, and it would seem that the main stream can only be tapped either by another boring further north, or by a lateral shaft from the present bore running northward till it encounters the current. There remains, of course, the further and open question as to whether the saline stream formerly passing through the Spa shaft, still continues its former north-westerly course, after having the outlet afforded by that shaft. Would it not be more in accordance with the law of nature that the stream should take the course of least resistance by rising in the well, and not flowing further along the bed of its special original stratum? If that be so, the only chance of another well would be to bore south-eastward of the Spa; and probably the shaft sunk by the late Mr. Blyton beside Coalpit Wood, if it had been continued, would have proved a safer venture than any other as yet attempted. At some future time we may have the wolf disturbing the stream, above the lamb represented by the original well, to the detriment of the latter. It may be here noticed that in the Scarle boring, as we are told, there was found a strong spring in the upper part of the lower Keuper sandstone at the depth of 790ft., and a still stronger spring at the base of that formation at 950ft. In that case, therefore, as also at Woodhall, the water was found in sandstone, but at a much greater depth, and also in sandstone of a different character, viz., the Keuper at Scarle, the Northampton at Woodhall. Another difference is that in the
Scarle strata we pass at once from the surface drift to the lower Lias; the Kimeridge clay and all the Oolite formations, which are found at Woodhall, with a thickness of some 630ft., being entirely absent. These differences, of course, illustrate the fact that, owing to abrasion and other causes, not only do the strata underlying the surface drift vary in different localities, but their several thicknesses vary; while, as at Harrogate, the mineral properties of the water also vary at a distance of only a few yards. Pass beyond the limits of the particular stream, and, below ground as well as above it, you are not “in the swim.”
In the spring of 1904, Mr. R. A. Came, of the Royal Hotel, commenced sinking a shaft, in search of the Spa water, at a point some ¾ mile south of the original well; and early in 1905 water was struck at a depth of 492 feet, which proved to have the same saline properties, with the addition of Epsom salt, a good supply issuing from the spongy sandstone. This opens up a vista of great possibilities in the future; it does away with the monopoly hitherto existing, and may have a most important effect, in the further development of the Spa. The well is 7ft. in diameter, is bricked to a depth of 495ft., and sunk to 520ft. The boring was carried out by Mr. Joseph Aldridge, of Measham, near Atherstone, Warwickshire, an expert mining engineer. Many fine fossils, as ammonites, belemnites, and bi-valves, were found in the different strata that were pierced.
I now proceed to remark upon some of the geological strata, as found at Woodhall. And first, after the mere surface gravel, we have the Boulder clay. This has a very interesting history. In the “Life of Nansen,” the Arctic traveller, it is stated [87a] that the geological strata of the Arctic regions show that at some remote period the climatic conditions were the reverse of those which prevail now. Throughout those regions, at present of intense cold, there was quite a southern climate, in which walnut trees, magnolias, vines, etc., flourished; while, on the other hand, there was also a period during which our own country, and large parts of the Continent, lying in the same latitude, were buried under vast ice-fields with an Esquimaux climate. It is there further stated [87b] that boulders are
found scattered over Norway, Sweden, and Denmark, which have been transported thither on glaciers, from regions still further north. In like manner glaciers at one time also spread over what are now Scotland and a great part of England, bringing along with them boulders from Norway, and Scandinavia generally. The present condition of Greenland, with its vast glaciers, pouring through its valleys, down to the water’s edge, on the sea shore, illustrates the condition of our own country at that remote period. [88a] As regards this country, these ice-streams may be classed under two distinct heads, (a) the native, inland glaciers, and (b) the north-eastern, Scandinavian glacier. To speak first of the former. As the climate, from causes into which we cannot here enter, [88b] gradually became coldier, glaciers were formed among the rugged hills in the present lake country of Cumberland and Westmoreland, some of which pushed their way westward, literally inch by inch, until they debouched in the Irish Sea, and filled it to overflowing, for it is only shallow. From Borrowdale, Buttermere, Eskdale, and other head centres, they also streamed southward and eastward. There was an immense central stream, which forced its way over the wild tract of Stainmoor (named doubtless from the thousands of boulders with which it is strewn); then, fed by lateral branches from many directions, it traversed Teesdale, turned towards the coast, passing by Scarborough, and so on to Holderness and the Humber, a branch also filling up Airedale and the Vale of York. [88c] From Holderness it passed the Humber, into Lincolnshire. Its most eastern limb would doubtless have debouched in the North Sea, and filled it; but here the north-eastern glacier, to which I have alluded, came into collision. Taking its rise in Scandinavia, it had spread into a vast sheet
in parts 3,000ft. thick, [89a] filled up the shallow North Sea, and the Baltic, a veritable mer de glace, and over-run northern Germany, its thickness even at Berlin being supposed to have been 1,300ft. Impinging on our eastern coast of Scotland and of northern England, it spread over a great part of Holderness, meeting and blending with the inland native glacier on the Humber; and the vast united ice-stream thence pursued its onward southern course, enfolding everything in its icy embrace, to the Thames and to the Severn. [89b] These great ice-streams created the geological formation called “The Drift,” or boulder-clay, which we have at Woodhall. The clay is simply the detritus, produced by the grinding, through long ages, of the rocks under the vast and weighty ice-fields slowly moving over them, and the abrasion of the hill-sides which they scraped in their course. The boulders are detached fragments, which fell from various rocky heights overhanging the ice-stream, rested on the surface of the ice-sheet, were borne along by it through hundreds of miles, and when, in the course of ages untold, the climate became milder, and the glaciers gradually shrunk and eventually disappeared, these fragments, often bearing the marks of ice-scraping, and oftener rounded by ice-action, fell to the soil beneath, and remain to this day, to bear their silent witness to the course once taken by the giant ice-stream. The period through which this process was going on has been variously computed, from 18,000 years, according to the estimate of Major-General A. W. Drayson, F.R.A.S., who gives elaborate astronomical statistics in support of his views (Trans. Victoria Institute, No. 104, p. 260), to 160,000, as calculated by Mr. James Croll (“Climate and Time”). It is now generally held that there were more than one ice-age, with inter-glacial breaks. These boulders are abundant in our neighbourhood, and of all sizes.
They may be measured by inches or by yards. There is a good-sized one in the vicarage garden at Woodhall Spa, which the present writer had carted from Kirkby-lane, a distance of a mile and a half. There is a larger one lying on the moor, near the south-east corner of the Ostler Ground. The writer has one in his own garden, a large one, more than 6ft. in length by 3½ft. high, and 2½ft. thick. It took five horses to drag it from its position, a quarter of a mile distant. There are six visible in the parish of Langton, two or three large ones near Old Woodhall Church; several large ones in Thimbleby, Edlington, and elsewhere. Smaller ones are often to be seen placed at turns in the roads to prevent drivers running their vehicles into the bank, or used as foundations to old cottages or farm buildings; and still smaller specimens may be constantly picked up by the pedestrian, or the sportsman, in his rambles through the fields. Much interest has of late years been taken in these boulders, arising from the distinct classes of glaciers to which I have referred, and the consequent difference between the nature of the boulders, as well as the source from which they have come, according as they belong to the one class or the other; and our Lincolnshire Naturalists’ Union have now a special “boulder committee” engaged in the investigation of this subject.
The late Professor Sedgewick, of Cambridge (whose lectures the writer attended), was the first to notice that along the Holderness shore there were (as he says) “an incredible number of blocks of granite, gneiss, greenstone, mica, etc., etc., resembling specimens derived from various parts of Scandinavia.” [90] These, we now know, were dropped by the great Scandinavian glacier; and, along with the kinds of stone here named, there are also boulders of Rhombporphyry (the “Rhomben porphyry” of Norwegian geologists, from the neighbourhood of Christiana), Augite syenite, and several more, not of British origin. These boulders are now being searched for, and found in our own neighbourhood. On the other hand, there is the different class of boulders which were brought down by the native inland glaciers. These consist largely of igneous kinds. The rugged hills of the Lake district owe their origin to fire; and the boulders which the glaciers have transported correspond. The shap granite, for instance, which is probably one of the commonest of this
class, comes from the shap granite bed of Wastdale, in Cumberland. Boulders of this rock, as Mr. Kendall tells us, “passed over Stainmoor in tens of thousands,” [91a] to visit us in Yorkshire and Lincolnshire. Other kinds are Felspar porphyry from Eskdale, in Cumberland, Andesite from Borrowdale, Granophyr from Ennerdale and Buttermere, Quartz, Basalt, and several more from the crystalline formations in the Lake district. Several boulders of these rocks have also been found in our own neighbourhood; and doubtless more remain to reward the explorer. [91b] I have dwelt at some length on this particular formation—the boulder clay—because it is the most ready to hand; it lies on the surface, in many parts around us, within the ken of the ordinary visitor to Woodhall Spa. It may give an additional interest to his rambles in search of health, to know that he may, at any moment, pick up a boulder which has travelled further, and passed through more strange vicissitudes, than he can well have done himself; perhaps, with Shakespeare, to read “Sermons in Stones,” and to moralise on the brevity of human life, with all its ailments, compared with those ages untold, through which the pebble in his hand slowly [91c] travelled on its long, laborious journey, to rest at length as a constituent element of the locality, where he himself is seeking relief and recreation.
To the west of Woodhall Spa, beyond the Stixwould-road, near the vicarage, and northward, the surface sand, in some parts, at the depth of a foot, or slightly more, hardens into an ironstone, so compact that tree roots cannot penetrate it. In root-pruning or manuring apple-trees, I have found the tap-root stunted