Then appeared upon the scene the famous Lavoisier, he to whom the Convention refused a fortnight's reprieve from the guillotine, just as he was on the threshold of a probably sublime discovery in the science of light; Fouquier-Tinville returning him for answer that the Republic had no need of chemists and savants. In the presence of Lavoisier, Maillard, another jeweller, took three diamonds and closely packed them in powdered charcoal in an earthen pipe-bowl in a strong fire; and when the pot was taken out, there lay the diamonds in the powdered charcoal untouched. It was, however, gradually discovered that it was only by entirely shutting out the air, and therefore the oxygen with which the carbon combines, that the diamonds were preserved from burning; whereas by the simple admission of air, of which oxygen is a constituent part, diamonds burn just the same as common coal. This was proved by Lavoisier in 1776; and Davy subsequently shewed that the diamond contains no hydrogen. So, when the most precious object which the earth produces is burned, the gas formed from its combustion is just that which our fires and our gas-burners yield, and our own bodies too, by the combustion which attends their living; and, says Mr Streeter, 'the old fable of the maiden from whose lips fell diamonds, may have a really scientific basis after all.' It takes immense heat to burn a diamond, and if it were possible to collect the black material which covers the surface during the process, it would be found to be simply soot.
The origin of the diamond is still a matter of scientific investigation and dispute; and the various opinions concerning it may be collected under two heads: (1) The diamond is formed immediately from carbon or carbonic acid by the action of heat. (2) It is formed from the gradual decomposition of vegetable matter. The various methods by which the supporters of the respective theories suppose the transformation to have been wrought, are full of interest and suggestion. In Brazil it was discovered that the matrix of the diamond is itacolumite, and it is said that the gems obtained from itacolumite sandstone have rounded angles and corners, whilst those from the sandy schist are perfect crystals. 'If,' says Mr Streeter, 'this be a fact, we must believe that the agency which changed the sandstone into itacolumite acted also on the diamond.'
Whether in the mines or by the rivers, whose 'golden sands' are flecked with gems, in rich Brazil, the labour of procuring these beautiful gems is great, and large specimens are rarely found; so rarely, that big diamonds have their histories—terrible histories too often—like heroes and race-horses. They are weighed by the carat, a word which Mr Streeter considers to have been derived from the name of a bean, a species of Erythrina, which grows in Africa. 'The tree which yields this fruit is called by the natives "kuara" (sun), and both blossom and fruit are of a golden colour. The bean when dried is nearly always of the same weight, and thus in very remote times it was used in Schangallas, the chief market of Africa, as a standard of weight for gold. The beans were afterwards imported into India, and were then used for weighing the diamond.' It is estimated that in ten thousand diamonds rarely more than one weighing twenty carats is met with, while possibly eight thousand of one carat or less may be encountered. An elaborate system of rewards and punishments is adopted in the Brazilian mining and river-searching works; but it is believed that in spite of this, one-third of the produce is surreptitiously disposed of by the labourers.
The histories of those world-famous diamonds the Sancy, the Regent, the Koh-i-noor, the Blue (or Hope) diamond, and others, have been related before, and history and romance have dealt with the misery and crime, the evil passions and the mystic fancies, involved in the stories of some of these. In a few lines Mr Streeter gives a sketch of the Brazilian contribution to this many-chaptered story, which is not generally known. 'The discovery of these precious stones in 1746,' he says, 'proved a great curse to the poor inhabitants of the banks of the diamond rivers. Scarcely had the news of the discovery reached the government, ere they tried to secure the riches of these rivers for the crown. To effect this, the inhabitants were driven away from their houses to wild far-away places, and deprived of their little possessions. Nature itself seemed to take part against them: a dreadful drought, succeeded by a violent earthquake, increased their distress. Many of them perished; but those who lived to return on the 18th May 1805, were benevolently reinstated in their rightful possessions. Strange to say, on their return the earth seemed strewn with diamonds. Often the little ones would bring in between three and four carats of diamonds.'
Next to the diamond comes the oriental ruby, and in former days it was more prized than the gem, which has a genus all to itself. The ancients gave immense sums for fine specimens of the ruby variety of 'corundum,' or aluminous stone. In Benvenuto Cellini's time a perfect ruby of a carat weight cost eight hundred crowns, whilst a diamond of like weight cost only one hundred. The two most important rubies ever known in Europe were brought to England in 1875. One was a dark-coloured stone, cushion-shape, weighing thirty-seven carats; the other a blunt drop-shape of 471/16 carats. Mr Streeter thinks that the London market would never have seen these truly royal gems but for the poverty of the Burmese government; and adds an interesting account of the estimation in which rubies are held in the distant Land of the White Elephant. The sale of the two rubies caused such excitement that a military guard had to escort the persons who conveyed the precious packet to the vessel. No regalia in Europe contains two such rubies. The smaller was sold abroad for ten thousand pounds; the larger has also found a purchaser, but Mr Streeter does not tell us at what price. The great ruby of the kings of Burmah is said to be as large as a pigeon's egg, and of wondrous quality; but is a treasure which no European eye has ever seen. Very few rubies pass out of the country; the king is excessively fond of these gems, and prohibits the export of them. The Burmese have strange notions about rubies; 'they believe that they ripen in the earth; that they are at first colourless and crude, and gradually become yellow, green, blue, and last of all red—this being considered the highest point of beauty and ripeness.'
The sapphire, the emerald, and the opal (the last erroneously supposed to exist in India, whereas it is found almost entirely in Hungary), the turquoise, and the cat's-eye (a rare variety of the chrysoberyl, and inferior in hardness to the diamond and sapphire only), are, each in its turn, the subjects of Mr Streeter's lucid and learned exposition; after which he passes to the less valuable classes, pearls, onyx, and the gems used for engraving and other purposes. The increasing estimation in which the true Ceylonese cat's-eye is held (it is one of the most fashionable gems at present, and there are specimens in the market worth upwards of one thousand pounds), renders the following particularly interesting: 'In India the cat's-eye has always been much prized, and is held in peculiar veneration as a charm against witchcraft. It is the last jewel a Cingalese will part with. The specimens most esteemed by the Indians are those of a dark olive colour, having the ray so bright on each edge as to appear double. It is indeed wonderfully beautiful with its soft deep colour and mysterious gleaming streak, ever shifting, like a restless spirit, from side to side as the stone is moved; now glowing at one spot, now at another. No wonder that an imaginative and superstitious people regard it with awe and wonder, and believing it to be the abode of some "genius" or djinn, dedicate it to their gods as a sacred stone.'
[THE INN AT BOLTON.]
When I was a little boy—I am now an old man of sixty—'Aunt Oliver,' as we used to call my father's widowed sister, was in the habit of paying long visits at my father's house. She had not long been a widow; and though past the meridian of life, was still a beautiful woman. But what made her so exceedingly popular with all my father's children was her repeated kindnesses, displayed to us in the shape of various useful and ornamental gifts, carefully chosen to suit our several ages and characters; but above all, her wonderful condescension in giving up her own pursuits on many a winter's night, that she might recount to us, as we sat grouped around the nursery fire, some of the incidents of her varied and eventful life. She had been a great traveller in her day, having been to Rome, and even visited the Holy Land; and what is more, she had written a book of travels! a circumstance which caused us to regard her with a strange curiosity almost amounting to awe; a feeling on our part which, but for her uniform kindness, might have detracted from that universal love we one and all bore towards her. One of my aunt's adventures made a strong impression on my youthful mind, and is even now, after a lapse of half a century, still fresh in my recollection. Thinking it might serve to divert those who have a fancy for the humorous, I have gathered up the threads of the story from the storehouse of my memory, and now present it in narrative form, under the foregoing title.
My uncle, Mr Oliver Brown, was in the iron trade; and in connection with his business, which was a very large one, was in the habit of paying periodical visits to the manufacturing town of Bolton, near to which his principal iron-works were situated. He usually paid these visits alone; but on the occasion of which I am about to speak he was accompanied by my aunt, who deemed it her duty to be with her husband, as it was winter-time and he had only just recovered from a severe illness. It was late in the evening of a bleak November day that the coach which conveyed Mr and Mrs Oliver Brown from their comfortable country-seat, distant some fifty miles from Bolton, entered the noisy ill-paved streets of that bustling town, and proceeded to what at that period was the principal inn of the place. Both travellers were tired by their journey, and after a hasty dinner, were glad to retire to rest.