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A History of Inventions, Discoveries, and Origins, Volume I (of 2)
A History of Inventions, Discoveries, and Origins, Volume I (of 2)

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A History of Inventions, Discoveries, and Origins, Volume I (of 2)

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Язык: Английский
Год издания: 2017
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A few days after Euler had read this paper of Unger’s before the Academy, M. Sulzer informed Hohlfeld of the invention, and advised him to exert his ingenuity in constructing such a machine. In two weeks this untaught mechanic, without having read Unger’s paper, and even without inspecting the figures, completed the machine, which Unger himself had not been able to execute through want of an artist capable of following his ideas.

Unger’s own description of his invention was printed, with copper-plates, at Brunswick, in the year 1774, together with the correspondence between him and Euler, and other documents. A description of Hohlfeld’s machine, illustrated with figures, was published after his death by Sulzer, in the new memoirs of the Academy of Berlin, 1771, under the title of ‘Description of a machine for noting down pieces of music as fast as they are played upon the harpsichord.’ Sulzer there remarks, that Hohlfeld had not followed the plan sketched out by Unger, and that the two machines differed in this – that Unger’s formed one piece with the harpsichord, while that of Hohlfeld could be applied to any harpsichord whatever.

When Dr. Burney visited Berlin, he was made acquainted with Hohlfeld’s machine by M. Marpurg; and has been so ungenerous, or rather unjust, as to say in his Musical Travels, that it is an English invention, and that it had been before fully described in the Philosophical Transactions. This falsehood M. Unger has sufficiently refuted. Without repeating his proofs, I shall here content myself with quoting his own words, in the following passage: – “How can Burney wish to deprive our ingenious Hohlfeld of the honour of being the sole author of that invention, and to make an Englishman share it with him, because our German happened to execute successfully what his countryman Creed only suggested? Such an attempt is as unjust in its consequences as it is dishonourable to the English nation and the English artists. When we reflect on the high estimation in which music is held in England, the liberality of the English nobility, and their readiness to spare no expenses in bringing forward any useful invention, a property peculiar to the English, it affords just matter of surprise that the English artists should have suffered themselves to be anticipated by a German journeyman lace-maker. To our Hohlfeld, therefore, will incontestably remain the lasting honour of having executed a German invention; and the Germans may contentedly wait to see whether Burney will find an English mechanic capable of constructing this machine, from the information given by his countryman Creed.”

REFINING GOLD AND SILVER ORE BY QUICKSILVER

AMALGAMATION

It is well known that quicksilver unites very readily with almost all metals, and when added in a considerable quantity forms with them a paste which can be kneaded, and which is called amalgam. On the other hand, as it does not unite with the earths, being a metallic substance, it furnishes an excellent medium for separating gold and silver from the substances with which they are found. The amalgam is squeezed through a piece of leather, in which these precious metals remain with a certain portion of the quicksilver; and the former are freed from the latter by means of fire, which volatilizes the mercury. This amalgam made with gold serves also for gilding metals (water-gilding)28, if it be rubbed over them, and afterwards heated till the quicksilver be driven off.

The first use of quicksilver is commonly reckoned a Spanish invention, discovered about the middle of the sixteenth century; but it appears from Pliny, that the ancients were acquainted with amalgam and its use, not only for separating gold and silver from earthy particles, but also for gilding29. Vitruvius describes the manner of recovering gold from cloth in which it has been interwoven. The cloth, he says, is to be put into an earthen vessel, and placed over the fire, in order that it may be burnt. The ashes are to be thrown into water, and quicksilver added to them. The latter attracts the particles of the gold, and unites with them. The water is then to be poured off, and the residue put into a piece of cloth; which being squeezed with the hands, the quicksilver, on account of its fluidity, oozes through the pores, and the gold is left pure in a compressed mass30. Isidore of Seville says also, that quicksilver is best preserved in vessels of glass, as it penetrates all other substances; and that without it neither silver nor brass can be gilded31. Modern mineralogists however have this advantage over the ancient, that they know how to separate the quicksilver from gold and silver without losing it. Instead of exposing the amalgam to an open fire, as formerly, and driving off the volatile metal, it is now put into a retort, and the quicksilver is collected in a receiver for further use.

Those also who wash gold from the sand found near rivers, use quicksilver before their work is completed; and I am strongly inclined to believe that this method prevailed in Germany long before the discovery of the mines in America. In the year 1582, John Michael Heberer described the washing of gold as he saw it practised at Selz, not far from Strasburg; and at that time quicksilver had been long employed for that purpose. In Treitlinger’s Dissertation, also, concerning the collecting of gold, and particularly in the Rhine, there is a description of the manner in which gold sand is washed by means of quicksilver, but no date is mentioned32.

The history of employing mercury in procuring the American silver is, as far as I know, most fully given by the Jesuit Acosta33, whose relation of the Indies abounds with curious and useful information. The quicksilver mines of Peru are situated in an extensive ridge of mountains near Guamanga, on the south side of Lima, and at no great distance from it. They are called Guancabelica, or Guancavilia. The mines were discovered about the year 1566 or 1567, when Castro was viceroy of Peru, by Henry Garces, or Graces, as he is called by the Portuguese. This man was a native of Porto, went to Peru in the Spanish service, and after the death of his wife became canon of the cathedral of Mexico. He translated the Lusiad of Camoens from the Portuguese into Spanish, and this has procured him a place in Professor Dieze’s translation of Velasquez’s History of Spanish Poetry. He caused a law to be enacted that no silver bullion should be suffered to circulate in Peru; but his greatest service was the discovery of the quicksilver mines. As he was one day examining the red earth, which the Indians use for paint, and call limpi, he observed that it was native cinnabar; and as he knew that quicksilver was extracted from it in Europe, he went to the place where it was dug up, made some experiments, and thus laid a foundation for the most important works. No one however thought of employing this metal in the silver mines till the year 1571, when Francis de Toledo being viceroy, one Pero Fernandes de Velasco came to Peru, and offered to refine the silver by mercury, as he had learnt at the smelting-houses in Mexico. His proposal being accepted, and his attempts proving successful, the old methods were abandoned, and that of amalgamation was adopted in its stead34. From this account it appears that Garces was not the inventor of amalgamation, that it was introduced into Peru in the year 1571, and that it had been long before practised in Mexico; but at what period it was first used there I have not been able to learn. The abbé Raynal says, that quicksilver was a free article of trade till the year 1571, when it was declared to belong exclusively to the crown; and this regulation was made in consequence of its being employed in refining. Robertson, in his History of America, tells us that the mines of Guanacabelica were discovered in 1563, and that amalgamation was introduced in 1574.

Anderson says, in his History of Commerce35, that in the second volume of Hakluyt there is a letter which shows the use of quicksilver to have been a new invention in the year 1572. This letter I found, not in the second, but in the third and last volume of the Voyages collected by Hakluyt36. It was written in the above year by a merchant named Henry Hawks, and contains only the following information: “A good owner of mines must have much quicksilver; and as for this charge of quicksilver, it is a new invention, which they find more profitable than to fine their ore with lead.”

Gobet, in a work entitled The Ancient Mineralogists of France, accuses Alphonso Barba of asserting that he found out amalgamation in the year 1609. To examine this charge, it will be necessary to give some account of the metallurgic works of that Spaniard, which, perhaps, may not prove unacceptable to those who are fond of metallurgy and mineralogy. Alvaro Alphonso Barba was born at Lepe, a small town in Andalusia, and officiated many years as clergyman of the church of St. Bernard, at Potosi. The first edition of this work was printed in quarto, at Madrid, in 1640, in the Spanish language, and illustrated with cuts. This book the Spaniards for a long time concealed, because they considered it as containing all their metallurgic secrets; though at that time there were much better works of the kind in Germany, and though amalgamation had been long known and practised. Edward earl of Sandwich, being ambassador to Spain, found however an opportunity of procuring a copy of it, as a great rarity; and he began a translation of it into English, but translated only the first two books. This translation was published at London in octavo, in 1674, after the earl’s death, and entitled The First Book of the Art of Metals, in which is declared the manner of their generation, and the concomitants of them. Written in Spanish by Albaro Alonso Barba, translated by the earl of Sandwich. From this English edition several German translations have been made, of which I am acquainted with the following: two at Hamburg, one printed in 1676, and the other in 1696; and two at Frankfort, one in 1726, and another in 1739. In the year 1749 a new edition appeared at Vienna. This edition, which is very different from any of the former, was translated from the French by one Godar, who was not a German, and who on that account apologises in the preface for the badness of his style. All these editions however are imperfect; for the original contains five books, as we learn from Leibnitz, who caused them to be transcribed. In the year 1751 a new translation came out at Paris, entitled Metallurgy, or the art of extracting and purifying metals, translated from the Spanish of Alphonso Barba, by M. Gosfort, with the most curious dissertations on mines and metallic operations; of this translation the celebrated abbé Lenglet de Fresnoy is said to have been the editor37.

To judge by two of the German editions, Gobet has done Barba an injustice. In that of 1676, I find Barba expressly says he does not believe the ancients were acquainted with the art of extracting silver from pounded ore by the means of quicksilver. This certainly does not indicate that he laid claim to the invention; besides, he everywhere speaks of amalgamation as an art long used in America, but complains of the negligence with which it was practised. In a passage however in the Vienna edition, and which has probably been added by Gobet, we are told that in the year 1609, Barba attempted to fix quicksilver, and with that view bethought himself of mixing it with finely pounded silver ore; that he at first imagined, with surprise, that he had obtained a mass of silver, but that he soon perceived that the mercury was not changed into silver, but had only attracted the particles of that metal. “I was,” adds Barba, “highly pleased with my new discovery of managing ore, of extracting its contents, and of refining it; and this method I continued to practise.” I imagine that Barba was still in Europe in 1609, and made that experiment before he was acquainted with the smelting-works in America. I am however of opinion, that one will see by the original that Barba did not wish to claim the invention of amalgamation as practised in the mines of America.

COLD OR DRY GILDING

Dry gilding, as it is called by some workmen, is a light method of gilding, by steeping linen rags in a solution of gold, then burning them; and with a piece of cloth dipped in salt water, rubbing the ashes over silver intended to be gilt. This method requires neither much labour nor much gold, and may be employed with advantage for carved work and ornaments. It is however not durable.

I am of opinion that this manner of gilding is a German invention, and that foreigners, at least the English, were first made acquainted with it about the end of the last century; for Robert Southwell describes it in the Philosophical Transactions for the year 1698, and says that it was known to very few goldsmiths in Germany.

GOLD VARNISH

As mankind could not have everything that they wished for of gold, they were contented with incrusting many articles with this precious metal. For that purpose the gold was beat into plates, with which the walls of apartments, dishes, and other vessels were covered. In early ages these plates were thick, so that gilding in this manner was very expensive38; but in process of time the expense was much lessened, because the art was discovered of making these gold plates thinner, and of laying them on with a size. Articles however ornamented in this manner were still costly, and the valuable metal was always lost. Yellow golden colours of all kinds were then tried; but these did not fully produce the required effect, as they wanted that splendour peculiar to metals, and appeared always languid and dull. It was not till modern times that artists conceived the idea of overlaying with silver, or some cheaper white metal, such things as they wished to have the appearance of gold, and then daubing them over with a yellow transparent varnish, in order to give to the white metal the colour of gold, and to the colour the splendour of metal. “When we cover our houses with gold,” says Seneca, “do we not show that we delight in deception? for we know that coarse wood is concealed under that gold39.”

This ingenious process, which at present is employed all over Europe in gilding wooden frames, coaches, and various articles, and which was formerly used in the preparation of the now old-fashioned leather tapestry, was invented towards the end of the 17th century. Anderson, in his Historical and chronological deduction of the Origin of Commerce, says that it was introduced into England by one Evelyn in the year 1633; and quotes, in support of this assertion, The Present State of England, printed in 1683.

This invention, however, does not belong to the English, but to the Italians, and properly to the Sicilians. Antonino Cento, an artist of Palermo, found out the gold varnish, and in the year 1680 published there an account of the method of preparing it. That work I have never seen; but I found this information in a book printed at Palermo in 1704, and entitled The Inventions of the Sicilians40. Among the few important things contained in this book, the greater part of which is compiled from old Latin writers, there is, in the additions, a receipt how to prepare the gold varnish (vernice d’oro). The whole account I shall transcribe, as the authors of the French Journal of Agriculture, Commerce, and the Arts, thought it worth their trouble to make it known in that work in 1778.

“Take shell-lac, and having freed it from the filth and bits of wood with which it is mixed, put it into a small linen bag, and wash it in pure water, till the water no longer becomes red; then take it from the bag and suffer it to dry. When it is perfectly dry, pound it very fine; because the finer it is pounded the more readily will it dissolve. Then take four parts of spirit of wine, and one of the lac, reduced, as before directed, to an impalpable powder, so that for every four pounds of spirit you may have one of lac: mix these together, and, having put them into an alembic, graduate the fire so that the lac may dissolve in the spirit. When dissolved, strain the whole through a strong piece of linen cloth; throw away what remains in the cloth, as of no use, and preserve the liquor in a glass bottle closely corked. This is the gold varnish which may be employed for gilding any kind of wood.

“When you wish to use it, you must, in order that the work may be done with more smoothness, employ a brush made of the tail of a certain quadruped called the vari, well-known to those who sell colours for painting; and with this instrument dipped in the liquor wash gently over, three times, the wood which has been silvered. You must, however, remember every time you pass the brush over the wood to let it dry; and thus your work will be extremely beautiful, and have a resemblance to the finest gold.”

After this invention was made known, it was not difficult to vary, by several methods, the manner of preparing it. Different receipts, therefore, have for that purpose been given in a number of books, such as Croker’s Painter, and others: and, on this account, young artists are frequently at a loss which to choose; and when a receipt is found better than another, experienced artists keep it always secret.

With the preparation of that varnish used for gilding leather tapestry Reaumur was acquainted, and from his papers it was made known by Fougeroux de Bondaroy. The method of making the English varnish was communicated by Scarlet to Hellot, in the year 1720; and by Graham to Du Fay, in 1738. In the year 1761, Hellot gave the receipt to the Academy of Sciences at Paris, who published it in their memoirs for that year.

If it be true, as Fougeroux says, that gilded tapestry was made above two hundred years ago, it might be worth the little trouble that such an examination would require to investigate the method used to gild it.

TULIPS

The greater part of the flowers which adorn our gardens have been brought to us from the Levant. A few have been procured from other parts of the world; and some of our own indigenous plants, that grow wild, have, by care and cultivation, been so much improved as to merit a place in our parterres. Our ancestors, perhaps, some centuries ago paid attention to flowers; but it appears that the Orientals, and particularly the Turks, who in other respects are not very susceptible of the inanimate beauties of nature, were the first people who cultivated a variety of them in their gardens for ornament and pleasure. From their gardens, therefore, have been procured the most of those which decorate ours; and amongst these is the tulip.

Few plants acquire through accident, weakness, or disease, so many tints, variegations, and figures, as the tulip. When uncultivated, and in its natural state, it is almost of one colour, has large leaves, and an extraordinary long stem. When it has been weakened by culture, it becomes more agreeable in the eyes of the florist. The petals are then paler, more variegated, and smaller; the leaves assume a fainter or softer green colour: and this masterpiece of culture, the more beautiful it turns, grows so much the weaker; so that, with the most careful skill and attention, it can with difficulty be transplanted, and even scarcely kept alive.

That the tulip grows wild in the Levant, and was thence brought to us, may be proved by the testimony of many writers. Busbequius found it on the road between Adrianople and Constantinople41; Shaw found it in Syria, in the plains between Jaffa and Rama; and Chardin on the northern confines of Arabia. The early-blowing kinds, it appears, were brought to Constantinople from Cavala, and the late-blowing from Caffa; and on this account the former are called by the Turks Cavalá lalé, and the latter Café lalé. Caval is a town on the eastern coast of Macedonia, of which Paul Lucas gives some account; and Caffa is a town in the Crimea, or peninsula of Gazaria, as it was called, in the middle ages, from the Gazares, a people very little known42.

Though florists have published numerous catalogues of the species of the tulip, botanists are acquainted only with two, or at most three, of which scarcely one is indigenous in Europe43. All those found in our gardens have been propagated from the species named after that learned man, to whom natural history is so much indebted, the Linnæus of the sixteenth century, Conrad Gesner, who first made the tulip known by a botanical description and a figure. In his additions to the works of Valerius Cordus, he tells us that he saw the first in the beginning of April 1559, at Augsburg, in the garden of the learned and ingenious counsellor John Henry Herwart. The seeds had been brought from Constantinople, or, according to others, from Cappadocia. This flower was then known in Italy under the name of tulipa, or tulip, which is said to be of Turkish extraction, and given to it on account of its resembling a turban44.

Balbinus asserts that Busbequius brought the first tulip-roots to Prague, from which they were afterwards spread all over Germany45. This is not improbable; for Busbequius says, in a letter written in 1554, that this flower was then new to him; and it is known that besides coins and manuscripts he collected also natural curiosities, and brought them with him from the Levant. Nay, he tells us that he paid very dear to the Turks for these tulips; but I do not find he anywhere says that he was the first who brought them from the East.

In the year 1565 there were tulips in the garden of M. Fugger, from whom Gesner wished to procure some46. They first appeared in Provence, in France, in the garden of the celebrated Peyresc, in the year 161147.

After the tulip was known, Dutch merchants, and rich people at Vienna, who were fond of flowers, sent at different times to Constantinople for various kinds. The first roots planted in England were sent thither from Vienna, about the end of the sixteenth century, according to Hakluyt48; who is, however, wrong in ascribing to Clusius the honour of having first introduced them into Europe; for that naturalist only collected and described all the then known species.

These flowers, which are of no further use than to ornament gardens, which are exceeded in beauty by many other plants, and whose duration is short and very precarious, became, in the middle of the 17th century, the object of a trade such as is not to be met with in the history of commerce, and by which their price rose above that of the most precious metals. An account of this trade has been given by many authors; but by all late ones it has been misrepresented. People laugh at the Tulipomania49, because they believe that the beauty and rarity of the flowers induced florists to give such extravagant prices: they imagine that the tulips were purchased so excessively dear in order to ornament gardens; but this supposition is false, as I shall show hereafter.

This trade was not carried on throughout all Europe, but in some cities of the Netherlands, particularly Amsterdam, Haarlem, Utrecht, Alkmaar, Leyden, Rotterdam, Hoorn, Enkhuysen, and Meedenblick; and rose to the greatest height in the years 1634–3750. Munting has given, from some of the books kept during that trade, a few of the prices then paid, of which I shall present the reader with the following. For a root of that species called the Viceroy the after-mentioned articles, valued as below expressed, were agreed to be delivered: —



These tulips afterwards were sold according to the weight of the roots. Four hundred perits51 of Admiral Leifken cost 4400 florins; 446 ditto of Admiral Von der Eyk, 1620 florins; 106 perits Schilder cost 1615 florins; 200 ditto Semper Augustus, 5500 florins; 410 ditto Viceroy, 3000 florins, &c. The species Semper Augustus has been often sold for 2000 florins; and it once happened that there were only two roots of it to be had, the one at Amsterdam and the other at Haarlem. For a root of this species, one agreed to give 4600 florins, together with a new carriage, two gray horses, and a complete harness. Another agreed to give for a root twelve acres of land; for those who had not ready money, promised their moveable and immoveable goods, houses and lands, cattle and clothes. A man whose name Munting once knew, but could not recollect, won by this trade more than 60,000 florins in the course of four months. It was followed not only by mercantile people, but also by the first noblemen, citizens of every description, mechanics, seamen, farmers, turf-diggers, chimney-sweeps, footmen, maid-servants and old clothes-women, &c. At first, every one won and no one lost. Some of the poorest people gained in a few months houses, coaches and horses, and figured away like the first characters in the land. In every town some tavern was selected which served as a ’Change, where high and low traded in flowers, and confirmed their bargains with the most sumptuous entertainments. They formed laws for themselves, and had their notaries and clerks.

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