A Manual of Electro-metallurgy: Including the Applications of the Art to Manufacturing ProcessesRichard Griffin and Company, 1860 - 166 من الصفحات |
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عبارات ومصطلحات مألوفة
action alloy ammonia applied arrangement battery black lead boiling brass bronze brush carbonate chloride clean coating colour connected copper plate copper solution covered crucible crystals current of electricity cyanide of potassium Daniell's deposited copper described dilute dipped dissolved earth battery effect electric current electro-metallurgy electrotype engraving experiments formed free cyanide fusible alloy galvanic German silver gilding give gold grains Grove's gutta percha heat hydrochloric acid immersed inches iron medal melted mercury method mixture mould muriatic acid negative nitrate nitric acid object obtained operation ounces oxide pairs of plates piece of copper plaster of Paris plating solution platinum pole porous cell portion positive electrode potash precipitate prepared quantity salt saturated silver solution Smee's solder solu solution of sulphate sulphate of copper sulphuric acid surface taken thickness tion varnish voltaic voltaic pile washed Wollaston's zinc and copper zinc plate
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الصفحة 6 - Petersburg)!, has also made a discovery which promises to be of little less importance to the arts. He has found a method — if we understand our informant rightly — of converting any line, however fine, engraved on copper, into a relief, by galvanic process.
الصفحة 20 - I had in my power to regulate at pleasure, by the thickness of the intervening wall of plaster of Paris, and by the coarseness or fineness of the material. I made...
الصفحة 90 - Niello. — Niello, a peculiar style of enamelling, consists in engraving or stamping figures on a plate of silver or gold, and then filling the incised lines, or impressed pattern, with a sort of enamel, differing, however, from true enamel, which is a kind of glass, by being formed of a mixture of the sulphurets of lead, silver and copper. This mixture is of a black color — hence the name niello, from nigellum, derived from niger, black — and when melted into the intaglio parts of a plate,...
الصفحة 13 - I applied heat, and then spirit of turpentine, to get off the cement ; and, to my satisfaction, I found that the voltaic copper had completely combined itself with the sheet on which it was deposited. " I then gave a plate a coating of cement to a considerable thickness, and sent it to an engraver : but when it was returned, I found the lines were cleared out, so as to be wedge-shaped, or somewhat in...
الصفحة 11 - When the cement was soft, the lines were pushed, as it were, into each other ; and when it was made of harder texture, the intervening squares of the net-work chipped off the surface of the metallic plate. However, those that remained perfect I put in action as before. In the progress of this experiment...
الصفحة 15 - On examination with a lens, every line was as perfect as the coin from which, it was taken. I was then induced to use the same piece again, and let it remain a much longer time in action, that I might have a thicker and more substantial mould, in order to test fairly the strength of the metal.
الصفحة 15 - Voltaic action took place, and the copper coin became covered with a deposition of copper in a crystalline form. But when about to make another experiment, and being desirous of using the piece of wire used in the first instance, I pulled it off the coin to which it was attached. In doing this, a piece of the deposited copper came off with it ; on examining the under portion of which, I found it contained an exact mould of a part of the head and letters of the coin, as smooth and sharp in every respect...
الصفحة 12 - ... and easily separated ; on the other hand, if I made them thicker, and of a little finer material, the action was slower, but the metallic deposition was as solid and ductile as copper formed by the usual methods, — indeed, when the action was exceedingly slow, I have had a metallic deposition apparently much harder than common sheet copper, but more brittle.
الصفحة 88 - This ring was cut asunder at one point, and the distance left between the severed parts was about the sixtieth of an inch. At the end of a few days (during which time the exciting liquors were several times renewed) the space in the severed portion of the ring was completely filled up with copper regulus, which had been precipitated ; and on partially cutting with a file through the part thus filled up, and examining it with a lens, it was observed to be very equally filled with solid and coherent...