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it is porous and brittle; and, when forged, too soft. The ancient weapons and utensils being of a hardness which this metal does not possess, it was long supposed that the ancients had some method of hardening copper, as we do iron and steel. But chemical analysis has shewn the falsity of this opinion, and demonstrated, that these weapons and instruments were not pure copper, but an alloy of this metal with tin, which we call bronze, and which was the es, brass, of the Romans. The weapons, instruments, and statues, which have been dug out of the ground, evidently prove, that the property of tin to impart hardness and density to the metal alloyed with it, was known and employed by the most ancient nations. All these objects occur of bronze, but none of pure copper. It is astonishing, that this prac tice of imparting to copper, by alloying it with a certain portion of tin, a hardness sufficient for sword-blades and other cutting. instruments, should have been so generally followed by the ancients, notwithstanding the want of tinmines. All the tin they used they were obliged to procure from the Cassiterides, the present Cornwall, and the trade was exclusively in the hands of the Phenicians.

Having had an opportunity of assaying several fragments of metallic antiquities, I conceive it may be of some utility to make public the results, as a supplement to the few accurate analyses hitherto made.

The fragments to be analysed, being first weighed, were put into a phial, into which were poured

six or eight parts of nitric acid of the specific gravity of 1.22, and digested in a sand-heat till completely dissolved. The contents of the phial were then diluted with a sufficient quantity of water, and the mixture left to stand till all the oxide of tin had fallen down, and the azure liquid appeared quite clear. This being poured off, the oxide of tin was collected, washed repeatedly with water, dried, heated red-hot, and weighed. It was found that 100 parts of calcined oxide of tin equalled 80 parts of tin in the metallic state. The nitric solution was tested in the usual way for silver, iron, lead, and zinc. When it was found free from these metals, as in all the following inquiries it proved, it was easy to calculate, by deducting the quantity of tin found, the proportion of copper, which was likewise obtained by the common methods.

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1. Analysis of an antique sword.

In a collection of antiquities at Berlin, found on digging into some ancient graves in the march of Brandenburg, among several articles of Bronze, as spear-heads knives, ornaments &c. are two swords: but the place where they were found, is not known. One of these swords was broken, the other entire. Their composition is the same: they are both covered with the green shining rust called patina. The sword in question weighs seventeen ounces, and is twenty inches long: the blade sixteen and a half, and the hilt which is rivetted, three and a half. The blade is two-edged, and one inch and a quarter broad for two

thirds of its length, the other third sloping off to a round point. In the middle it is three lines and a half thick, and slopes to form an edge on each side. Below the hilt, and on each side at the edge, is a part cut out nine or ten lines long, and one, or one and a quarter deep, the use of which I do not know.

To find the colour and brightness of the blade, I ground it; and though the parts injured by the rust prevented me from restoring its original appearance, its colour and lustre were observable in some parts, and indicated considerable hardness and density.

Its analysis, in the way above mentioned, gave the following proportions: copper 89, tin 11.

To render the description and analysis of these antique swords found in our country more interesting by a comparison with other weapons, I shall here give an abstract of two excellent papers by Mr. Mongez, in the fifth volume of the Memoirs of the Institute, which contain a description and analysis of similar bronze swords found near Abbeville. One was found under a bed of peat, with the skeletons of a man and horse. Its whole length was 22 inches, the breadth of the blade 16 lines, the weight 21 ounces. According to the analysis of Mr. Darcet, it contained 15.53 tin, and 87.57 copper. A second which was found at the depth of ten feet in a calcareous tufa, was about 29 inches long, and contained 15 tin and 85 copper. The rivets that fastened the outer part of the hilt contained but 5 per cent of tin, because they required to be more flexible. A third was 33 inches

long, and found at the depth of nine feet in a bed of peat, by the side of the skeleton of a man, on the head of which was a bronze helmet. This skeleton and several others were lying in an ancient boat. The composition of this sword was 10 tin, and 90 copper. Another sword or cutlass, eighteen inches and a half long contained but 4 per cent of tin.

These antique swords were not forged, like our weapons of iron and steel, but were cast in moulds, like all other instruments of bronze. Their edge, as well as those of cutting instruments in general, must have been given by hard smooth stones. The opinion of some antiquaries, therefore, who assert, that the ancients were unacquainted with the art of casting metals is absolutely false.

To say nothing of the nature of bronze, rendering it incapable of being prepared in any other way, any one may be convinced of this by simple inspection; if you would have a proof of it in Homer, you need only read the 23rd book of the Iliad.

2.

Analysis of the metallic alloy of crooked antique knives. In several provinces of Germany cutting instruments shaped like sickles, have been found in digging or ploughing the ground; but whether they really were ancient sickles is not determined, as many suppose that they may have been used as knives in the warm baths. I have selected two of these, found at different places, for analysis.

One, which was found with varions utensils in a garden at Merz, near Muelford, yielded by analysis, after its crust of greyish rust

was removed, tin 15 parts, copper 85.

The other, found in the island of Rugen, was covered with the common patina, and gave tin 13, copper 87.

3. Analysis of an antique ring. I had selected for other inquiries a fragment of an elastic and flexible ring, which was found with some Roman coins in the vicinity of the Rhine. This ring was made with a half-flattened stem, grooved on the outside, and eight lines broad. Its exterior diameter is two inches and seven-eighths, its interior two and a half. It is not soldered, but its extremities are so closed by the elasticity of the metal, that it is difficult to separate them. The colour of the metal, in the parts that have been polished, is very fine. We have no sufficient clue to the use of these rings. Its analysis gave tin 9, copper 91.

The same proportions were found in an elastic ring analysed by Mr. Mongez, which was found near Bourg, where several other Roman antiquities had before been

discovered.

It is to be wished that the elastic property of bronze should be examined more minutely.

4. Analysis of a piece of Grecian

brass.

This little fragment, decorated This little fragment, decorated with ornaments, which was found in Sicily in a Grecian tomb, appears to have been a button, or some other ornament of armour. Its proportions are, tin 11, copper 89.

5. Analysis of antique rivets. These rivets were short, and

of the thickness of a middle-sized wire. As it was necessary they should be flexible, it was requisite that the alloy should be in different proportions, that of the tin being diminished. This consisted of tin 2.25, copper 97.75.

6. Analysis of an antique cup.

The great number of antique cups and vases found at different times sufficiently prove, that the ancients possessed the art of reducing bronze to thin sheets. The cup, pieces of which were found in a Grecian tomb near employed for this analysis, was Naples. It has so well resisted little of its polish. Being very rust, that its inside has lost very thin, I expected to find in it but obtained tin 14, copper 86. a small proportion of tin; but I

tin found in the present analysis Comparing the proportions of with those of a fragment of an antique mirror, which I had already Vol. VI. and which consisted of published in Scherer's Journal, 32 per cent tin, and a little lead, ously adapted the proportions of we find that the ancients judiciwhich they were required. I contin and copper to the purposes for ceive it unnecessary to particu larize the rest of the analyses I it is sufficient to say, that except made of pieces of antique bronze: this mirror, and the rivets already mentioned, I always found the cent of tin. alloy contained from 9 to 15 per

7. Analysis of the quadriga of Chios.

The proportions of the alloy of this master-piece of antiquity bear no resemblance to those already

mentioned. It has been long asserted, that these horses were the work of Lysippus, contemporary of Alexander, who is known in the history of the arts as the greatest master in the execution of equestrian statues; but several modern connoisseurs dispute this, and say the horses are in too clumsy a style to have been the work of Lysippus.

It is admitted, however, that they were brought from Chios to Constantinople in the reign of Theodosius I. In 1204, when the croisaders made themselves masters of that city for the second time, pillaged it, and set it on fire, this quadriga escaped the destruction that befel many ancient works of art. On dividing the plunder, the doge Dandolo destined these horses for the republic of Venice. After his death, the podestat, Martin Zeno, sent them to Venice with other parts of the spoil, and the doge, Peter Ziani, ornamented with them the entrance to the cathedral of St. Mark. About six centuries after, in 1798, they were removed to Paris, and placed at the two entrances of the square of the Carrousel. Since that time they have been brought together again, and harnessed to a chariot, to decorate the triumphal arch in that square.

These four horses were not cast at once, like statues in bronze, but are composed of separate parts, wrought with the chisel, and afterward joined together. The hollows in the hind parts are filled with lead, which has assumed its shining reddish appearance. These parts are gilt; yet the gilding is nearly effaced, though, according to Buonarotti, the gold with which

the ancients covered their bronze was to ours as six to one.

These horses were supposed to be of copper, because this metal takes gilding better than bronze; and I have been enabled to verify the fact on a small piece, weighing 40 grains, which was sent me. From this it appears, that the copper was not absolutely pure, as it contained a little tin; but the oxide of tin obtained from these 40 grains, amounted only to 0-35 of a grain; so that when reduced to the metallic state, the proportion would be only 7 parts of tin to 993 of copper. This proportion is so small, it may be presumed to have been accidental.

In our days the use of iron and brass has singularly diminished that of bronze, which was so frequently employed by the ancients. It is now confined to cannons, bells, and statues. But is it not desirable, that our copper vessels should be replaced by vessels of bronze or brass, as they are less liable to oxidation, and to injure the health? This question deserves to be solved by comparative experiments. What ought to induce us to examine this important question is, that the ancients employed only vessels of bronze in their kitchens and cellars in general, though they were well acquainted with the injuriousqualities of oxide of copper taken internally. This oxide, however, they used externally for cleansing and healing wounds. According to Aristotle, wounds made with weapons of bronze were more easily cured than those made with weapons of iron.

In a note subjoined, Mr. Darcet

observes, that the metal of the horses of the Carrousel, taken as it is, yields copper, tin, lead, gold, and silver. If the surface be filed, so as to remove all the gilt part, nothing is found but copper, tin, and lead. If a piece perfectly free from cracks be taken, and thoroughly cleaned by the file, it yields copper and tin alone: but it is difficult to procure such pieces, for the copper is full of flaws, and the mixture of lead and tin, with which the horses were partly filled, has insinuated itself into every crack. On analysing some select pieces, he found copper 99.177, tin 0-823: but as sulphuric acid disturbed the transparency of the solution, he supposed a little lead was present, and that part of the tin might come from the alloy of tin and lead,' which had covered the inside of the pieces he used.

He could not procure a piece well gilt, to examine in what way the gold was applied; but he observes, that the brittleness of the metal seems to indicate that quicksilver was employed.

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The four last lines of the first epigram are omitted, as having no reference whatever to the subject.

From these passages, and from that of Pliny, in which he tells us that Tiberius, who was fond of cucumbers, had them in his garden throughout the year by means of (specularia) stoves, where they were grown in boxes, wheeled out in fine veather, and replaced in the nights or in cold weather, Pliny, book xix. sect. 23, we may safely infer that forcing-houseswere no unknown to the Romans, though they do not appear to have been caried into general use.

Flues the Romans were well acquainted with; they did not use open fires in their apartments as we do, but, in the colder countries at least, they always had flues un

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