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account given even of the nature of the pipe or hose is short and defective, probably with a view to render it more difficult to be imitated. It is only said that it was made of leather in a particular manner; and that, besides being thick, it was capable of resisting the force of the water.

The conveyer or bringer was invented also about the same time by these two Dutchmen. This name is given at present to a box which has on the one side a sucking-pump, and on the other a forcing-pump. The former serves to raise the water from a stream, well, or other reservoir, by means of a stiff leathern pipe, having at the extremity a metal strainer pierced with holes to prevent the admission of dirt, and which is kept suspended above the mud by a round piece of cork. The forcing-pump drives the water thus drawn up through a leathern pipe into the engine, and renders the laborious conveyance of water by buckets unnecessary.

At first, indeed, this machine was exceedingly simple. It consisted only of a leathern pipe screwed to the engine, the end of which widened into a bag supported near the reservoir, and kept open by means of a frame, while the labourers poured water into it from buckets. A pump, however, to answer this purpose was soon constructed by the Van der Heides, who named it a snake-pump. By its means they were able to convey the water from the distance of a thousand feet; but I can find no account of the manner in which it was made. From the figure, I am inclined to think that they used only one cylinder with a lever. Sometimes also they placed a portable pump in the water, which was thus drawn into a leathern hose connected with it, and conveyed to the engine. Every pipe or hose for conveying water in this manner they called a wasserschlange, water-snake, and this was not made of leather, like the hose furnished with a fire-pipe, but of sail-cloth. They announced, however, that it required a particular preparation, which consisted in making it water-tight by means of a proper cement. The pipe also, through which the water is drawn up, must be stiffened and distended by means of metal rings; otherwise the external air, on the first stroke of the pump, would compress the pipe, so that it could admit no water. It is here seen that pipes made of sail-cloth are not so new an invention as many have supposed. That our present apparatus for conveying water

to the fire-engine is much more ingenious, as well as convenient, must be allowed; but I would strongly recommend that in all cities there should be pumps, or running wells or water, to the spout of which pipes having one end screwed to a fire-engine might be affixed. The Van der Heides, among the advantages of their invention, stated that this apparatus rendered it unnecessary to have leathern buckets, which are expensive, or at any rate lessened their number, as well as that of the workmen.

From this account, the truth of which cannot be doubted, one may readily believe that engines with leathern hose were certainly not invented by Gottfried Fuchs, director of the fire apparatus at Copenhagen, in the year 1697, as publicly announced in 1717, with the addition, that this invention was soon employed both in Holland and at Hamburg. Fuchs seems only to have made known the Dutch invention in Denmark, on occasion of the great fire which took place on the 19th of April 1689, at the Opera-house of Amalienburg, when the beautiful palace of that name, and more than 350 persons were consumed. At any rate we are told in history, that, in consequence of this calamity, an improvement was made in the fire establishment, by new regulations issued on the 23rd of July 1689, and that engines on the Dutch construction, which had been used more than twelve years at Amsterdam, were introduced.

Hose or pipes of this kind for conveying water were however not entirely unknown to the ancients. At least the architect Apollodorus says, that to convey water to high places exposed to fiery darts, the gut of an ox, having a bag filled with water affixed to it, might be employed; for on compressing the bag, the water would be forced up through the gut to the place of its destination'. This was a conveyer of the simplest kind.

Among the latest proposals for improving the hose is that of weaving one without a seam. In 1720, some of this kind were made of hemp at Leipsic, by Beck, a lace-weaver, as we are told by Leupold, in his before-mentioned work on fireengines, which was printed the same year. After this they were made by Erke, a linen-weaver of Weimar; and at a later period they were made of linen at Dresden, and also in 1 Poliorcet. page 32.

Silesia'. In England, Hegner and Ehrliholzer had a manufactory at Bethnal-green, near London, where they made water-tight hose without seams2. Some of the same kind are

made by M. Mögling on his estate near Stutgard, on a loom of his own invention, and are now used in many towns of the duchy of Wirtemberg. I shall here remark, that Braun had a loom on which shirts could be wove without a seam, like those curious works of art sometimes brought from the East Indies, and of which he has given a full description with an engraving3.

In the last place, I shall observe, that notwithstanding the belief of the Turks in predestination, fire-engines are in use at Constantinople, having been introduced by Ibrahim Effendi.

[The fire-engines now in use are made upon the airchamber principle above-described. Mr. Braithwaite has applied steam-power to the working of fire-engines. On this principle a locomotive and a floating engine have been constructed. The former was first employed at a fire in the Argyle Rooms in 1830. It required eighteen minutes to elapse before the water in the boiler was raised to 212°, and threw up from thirty to forty tons of water per hour, to a height of ninety feet. Two others have been constructed by the same engineer, one of which threw up ninety tons of water per hour, and one made for the king of Prussia threw up about 613 tons per minute. In the steam floating engine which lies in the Thames, the machinery either propels the vessel, or works the pumps as required. The pipes used for conveying the water from the plugs to the engines are now constructed of leather, the seams being either sewed up or fastened with metallic rivets.]

Leipziger Intelligenzblatt, 1775, p. 345; and 1767, p. 69. Teutscher Merkur, 1783.

2 Lysons's Environs of London.

Vestitus Sacerdotum Hebræorum. Amst. 1701, 4to, i. p. 273. Much useful information in regard to various improvements in the apparatus for extinguishing fires may be found in Aug. Niemann Uebersicht der Sicherungsmittel gegen Feuersgefahren. Hamb. und Kiel, 1796, 8vo.

VOL.II.

S

INDIGO.

It is more than probable that indigo, so early as the time of Dioscorides and Pliny, was brought to Europe, and employed there in dyeing and painting. This I shall endeavour to show; but under that name must be understood every kind of blue pigment, separated from plants by fermentation, and converted into a friable substance by desiccation; for those who should maintain that real indigo must be made from those plants named in the botanical system Indigofera tinctoria,would confine the subject within too narrow limits; as the substance which our merchants and dyers consider as real indigo is prepared, in different countries, from so great a number of plants, that they are not even varieties of the same species.

Before the American colonies were established, all the indigo employed in Europe came from the East Indies; and till the discovery of a passage round the Cape of Good Hope, it was conveyed, like other Indian productions, partly through the Persian Gulf, and partly by land to Babylon, or through Arabia and up the Red Sea to Egypt, from which it was transported to Europe. Considering this long carriage, as the article was not obtained, according to the Italian expression, a drittura, that is, in a direct manner, it needs excite no surprise, that our knowledge, in regard to its real country and the manner of preparing it, should be exceedingly uncertain and imperfect. Is it astonishing that articles, always obtained through Arabia, should be considered as productions of that country; and that many commodities which were the work of art, should be given out to be productions of nature? For more than a hundred years the Dutch purchased from the Saxons cobalt, and smalt made from it, and sold them again in India; and the Indians knew as little where and in what manner the Dutch obtained them, as the Saxons did the peopie who were the ultimate purchasers and consumers. real nature of indigo was not generally known in Europe till the Europeans procured it from the first hand; yet long after that period, and even in the letters-patent obtained on the 23rd of December 1705, by the proprietors of the mines in the principality of Halberstadt and the county of Reinstein,

The

indigo was classed among minerals on account of which works were suffered to be erected; but this only proves the individual ignorance of the undertakers, and also of their superiors, when they read what they had written, and confirms the justness of Ovid's advice,

Disce bonas artes, moneo, Germana juventus;

Non tantum trepidos ut tueare reos.

What Dioscorides calls Indicon, and Pliny and Vitruvius Indicum, I am strongly inclined to believe to have been our indigo'. It was a blue pigment brought from India, and used both in painting and in dyeing. When pounded it gave a black powder, and when suspended in water it produced an agreeable mixture of blue and purple. It belonged to the costly dye-stuffs, and was often adulterated by the addition of earth. On this account, that which was soft without any roughness, and which resembled an inspissated juice, was esteemed the best. Pliny thinks that pure indigo may be distinguished from that which is adulterated by burning it, as the former gives an exceedingly beautiful purple flame, and emits a smell similar to that of sea-water. Both he and Dioscorides speak of two kinds, one of which adheres to reeds, in the form of slime or scum thrown up by the sea; the other, as Dioscorides says, was scraped from the sides of the dyepans in the form of a purple-coloured scum; and Pliny expressly remarks, that it was collected in this manner in the establishments for dyeing purple. The former relates also, that Indicum belonged to the astringent medicines; that it was used for ulcers and inflammations, and that it cleansed and healed wounds.

This is all, as far as I know, that is to be found in the works of the ancients respecting Indicum. I have given it at full length, as accurately as possible, and I have added, in order that the reader may be better able to compare and judge, references to the original words of the authors. Indicon, it is true, occurs in other passages; but it was certainly different from the one already mentioned. I allude, for example, to the black Indicon of Arrian and the Indicon of Hip-› pocrates. Of the former I shall treat in particular hereafter; 1 Dioscor. lib. v. cap. 107, p. 366. Περὶ Ἰνδικον.

* Plin. lib. xxxv. cap. 6, § 27, p. 688; and Isidorus, Origin. lib. xix. cap. 7, p. 464.

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