fine-fibrous, C. conchoidal, V.C. vitreous-conchoidal, F.C. fine-crystalline, C.C. coarse-crystalline. The tensile strength was determined on prisms inch square, without having been hammered or compressed after being cast; and the weights given are those which each prism just sustained for a few seconds before disruption.

"6. Approaching tombac in colour, is not quite so good for rolling, hammering, or wire drawing as common red brass, which contains less copper in proportion to the zinc.

"8. Comes very near 'red-brass,' which it quite equals with respect to its working qualities.

"10. The reddish colour is now beginning to pass into brass-yellow; it behaves itself irreproachably under the rolls and hammer, and in wire drawing.

"13. Working qualities quite the same as those of common brass. Karsten remarks that it was this alloy which was puffed for some time in England under the name of Mosaic gold.

"14. In working qualities not different from common brass.

"16. It contains 4 per cent more zinc and 4 per cent less copper than common brass. The colour is no longer pure brass-yellow, but has a reddish tint, works excellently under the rolls and hammer, as well as in wire drawing.

"19. Much to be recommended, on account of its golden colour, and though it possesses greater tenacity than the preceding, and less hardness, is brittle. Well adapted for cast ware. Very flexible after casting while still hot. When cold it is hard to cut, and is rather fractured than cut. The ingots after being cut, annealed, and cooled, can no longer be rolled. If, after heating and cooling to the temperature of boiling water, they are rolled, they produce only very brittle, fragile sheets, much cracked at the edges, notwithstanding that frequent annealing during rolling may have been resorted to; it is quite unsuitable for rolling, hammering, or wire drawing.

"20. Very flexible while strongly heated. Rolls tolerably

well cold, though it frequently cracks at the edges. During rolling into thin sheets, it requires more frequent annealing than common brass. It cannot be soldered, as it melts at the same temperature as the solder. It is not adapted for wire drawing.

"21. Fracture reticulated.

Possesses a tolerable degree of tenacity, but by hammering becomes so brittle that at no temperature can it be sufficiently drawn out for practical

purposes.

“22. The lustre is so imperfectly metallic, that it would hardly be recognised as a metallic alloy. Its great brittleness and frangibility, combined with its perfectly conchoidal and smooth fracture, communicate to the alloy more the appearance of a sulphur compound than that of a mixture of two metals.

"23. More brittle than the last; fracture smooth, even, small-conchoidal; lustre strongly metallic.

"25, 26, 27. Very brittle. Too hard to file or turn; lustre nearly equal to that of speculum metal.

"28, 29. Brittle. Too hard to file or turn; lustre nearly equal to that of speculum metal.

"30. Very brittle. Too hard to file or turn; lustre nearly equal to that of speculum metal.

"31. Barely malleable.

"32. Brittle; fracture granular, uneven; has a tolerable degree of tenacity, but cannot be worked under the rolls or hammer.

"33. Brittle.

"34. In external character and working qualities closely resembles No. 32.

"36. Brittle.

"38. Fracture finely granular.

"39. Has sufficient tenacity to admit of being somewhat extended under the rolls and hammer, if, after annealing, it is not allowed to become cold."