The Technical repository, by T. Gill

Front Cover
Thomas Gill (patent-agent)
1822
 

What people are saying - Write a review

We haven't found any reviews in the usual places.

Other editions - View all

Common terms and phrases

Popular passages

Page 14 - Now Know Ye, that in compliance with the said proviso, I, the said Adolphe Nicole, do hereby declare that the nature of my said Invention, and the manner in which the same is to be performed, are particularly described and ascertained in and by the following statement thereof, reference being had to the Drawing hereunto annexed, and to the figures and letters marked thereon...
Page 348 - ... experiments ought to be), the lime was seen to become rounded at the angles, and gradually to sink, till in the course of a few seconds only a small globular protuberance remained, and the mass of supporting lime was also superficially fused at the base of the column, through a space of half an inch in diameter.
Page 338 - The varnish, in a narrow-necked bottle, is to be applied to the middle of the flat face of the rubber, by laying the rubber on the mouth of the bottle, and shaking up...
Page 366 - He found, that, — in the production of Scheele's green, by arsenic, sulphate of copper and carbonate of potash, — chromate of potash might be substituted for the arsenic; and that it produced a precipitate not to be distinguished, by the eye, from Scheele's green. He ascertained, also, that even Mr. Hume's celebrated test, nitrate of silver, (as modified in its application by Dr. Marcet,) gave, with chromate of potash, a yellow precipitate; which, when placed side by side with one produced by...
Page 276 - I do not here consider. What I call attraction may be performed by impulse, or by some other means unknown to me. I use that Word here to signify only in general any Force by which Bodies tend towards one another, whatsoever be the Cause.
Page 196 - Patentee makes use of good cast steel, in preference to any other sort of steel, for the purpose of making plates, cylinders, circular or other dies, and more especially when such plates, cylinders, or dies are intended to be de-carbonated. For the reason given above, the steel is de-carbonated, solely for the purpose of rendering it sufficiently soft for receiving any impression intended to be made thereon. It is therefore necessary that, after any piece of steel has been...
Page 196 - The stratum of decarbonated steel should not be too thick for transferring fine and delicate engravings; for instance, not more than three times the depth of the engraving ; but for other purposes the surface of the steel may be decarbonated to any required thickness. To decarbonate it to a proper thickness for a fine engraving, it is to be exposed for four hours in a white heat, enclosed in a cast-iron box with a wellclosed lid.
Page 145 - I have already manufactured many thousand dozens for that purpose. The extra-stout Drawing-Papers, or Card-Boards, as they are usually denominated, are always made by pasting several sheets of paper together, in the manner of a common pasteboard, and afterwards bringing them to a smooth face by pressing and rolling. The pasting is a dirty operation, and the occasion of many defects, some of which are fatal to the degree of perfection and nicety required in a good drawingboard ; for it often happens...
Page 255 - ... of Welsh Pool, in Montgomeryshire. This material being freed from all adhering pieces of slate and of .quartz, is ground to a fine powder; and being thus prepared, I mix, .with 27 parts of felspar, 18 of borax, 4 of Lynn sand, 3 of nitre, 3 of soda, and 3 of Cornwall china clay. This mixture is to be melted to a frit; and is then to be ground to a fine powder, 3 parts of calcined borax being added previously to the grinding.
Page 339 - The cloth must next be wetted a little with spirit of wine and oil without varnish, and the surface being rubbed over with the precautions last mentioned until it is nearly dry, the effect of the operation will be seen ; and if it be found that it is not complete, the process must be continued, with the introduction of spirit of wine in its turn, as directed, until the surface becomes uniformly smooth, and beautifully polished.

Bibliographic information