206 Analyses of Books. [March, 



ail parts of the civilized world. Mr. Yarrington went over at th<> 

 expense of some public spirited individuals to learn the art of 

 making tin-plate. On his return to England many thousand 

 plates were made under his direction, v>'hich were considered by 

 all good judges as superior to the Saxon tin-plates. But he and 

 his partners were prevented from establishing a manufactory by 

 the conduct of Charles il. who granted a patent to one of his 

 courtiers for making tin-plate. This courtier did not possess 

 tlie requisite skill, and the patent prevented those wlio possessed 

 the skill from establishing the manufacture. Ihe art of making 

 tin-plate does not seem to have been practised in England till 

 about 1721). A manufactory was then established at Pontypool, 

 in Monmouthshire, where the art is still practised to a consider- 

 able extent. 



The best English bar iron (prepared with charcoal instead of 

 coke) is employed in this manufacture. It is rolled at the mill 

 by a peculiar process into plates of the requisite thinness. 

 These plates are then cut by hand shears, or by machinery, to 

 the requisite sizes. The plates are then bent into the form of 

 the Greek A, and put into a furnace, heated by flame from a fire- 

 place of a peculiar construction, after having been pi.eviously 

 cleansed, as it is called ; that is, steeped for four or five minutes 

 in a mixture of muriatic acid and water, in the proportion of four 

 pounds acid to three gallons water. 



In the oven they remain red-hot, standing upright on the floor 

 till the heat takes a scale off their surface. They are then taken 

 out, allowed to cool, straightened, and beaten smooth upon a 

 cast-iron block. The plates are then smoothed and polished by 

 passing them cold between a pair of cast-iron rollers properly 

 nardened and finely polished. 



These rollers are made by pouring the melted iron into a thick 

 cast-iron box. The consequence is, that the surface loses its 

 heat rapidly, and becomes hard, while the central part of the 

 roller remains soft. Ihe art of making these rolls, as they are 

 called, is imperfect, as the process often misgives. 



The plates thus smoothed are steeped for lU hours in the lies, 

 which is water acidulated by means of bran. In the lies, the 

 pi tes stand on their edges, and they are turned once, which is 

 'Called working the lies. The plates, being taken out of the lies, 

 are agitated for about an hour in a liquid composed of a mixture 

 of sulphuric acid and water. In this mixtL;re they become 

 perfectly bright, and free from the black spots which are always 

 on them when they are first immersed in it. 



When the plates come out of this pickle, they are put into 

 pure water and scoured in it, with hemp and sand to remove any 

 remaining oxide or rust of iron that may be still attached to them; 

 for wherever there is a particle of runt, or even of dust, upon 

 thera, there the tin will not fix. After being scoured, they are 



