126 



LINEN 



contains intact all the acetate of lead first employed, and may be used in the next 

 operation, after the addition to it as before of 1 8. ounces of litharge. 



By filtration through paper or cotton the oil may be obtained as limpid as water, 

 and by exposure to the light of the sun it may also be bleached. 



Should a drying oil be required absolutely free from lead, it may be obtained by 

 the addition of dilute sulphuric acid to the above, when, on being allowed to stand, 

 a deposit of sulphate of lead will take place, and the clear oil may be obtained free 

 from all trace of lead. 



Linseed oil was at one time much used in the preparation of a liniment, which, as 

 it is one of the very best possible applications to a burnt surface, cannot be too 

 generally known. If equal parts of limewater and linseed oil are agitated together, 

 they form a thick liniment, which may be applied to the burn with a brush or 

 feather. It relieves at once from pain, and forming a pellicle, protects the abraded 

 parts from the air. The Linimentum. calcis of the Pharmacopoeia is equal parts of 

 limewater and olive oil ; this is a more elegant, but a less effective preparation. 

 See OIL. 



XjIUTT for Surgery, was formerly prepared by scraping up linen by the hand ; the 

 preparation of it, however, has been made the subject of a patent by Mr. Thomas Boss, 

 which consists in the employment of peculiarly constructed scrapers for abrading the 

 surface of the linen cloth, and producing a pile or nap upon it. The scrapers 

 are worked by a rotary motion. 



Instead of rotary scrapers, a reciprocating pendulous movement is sometimes applied 

 to a single scraper. Chisel-formed blades are claimed by the patentee as scrapers for 

 raising the pile, by working with the bevel edges forwards, so as to scrape and noi to 

 cut the fabric. He has in the rotary form a ledge or bed concentric with the axis of 

 the scraper, which he also claims ; both of which seem to be serviceable. Several 

 kinds of lint-making machines are now employed, but as they all partake more or less 

 the above principles they do not require description. 



LIQUATION (Eng. and Fr. ; Saigcrung, Ger.) is the process of sweating out, 

 by a regulated heat, from an alloy a more easily fusible metal from the interstices of a 

 metal which is more difficult of fusion. Lead and antimony are the metals most com- 

 monly subjected to liquation : lead for the purpose of removing by its superior affinity 

 the silver present in any complex alloy ; antimony as an easy means of separating it 

 from its combinations in the ores. 



Figs. 1392, 1393, 1394, represent the celebrated antimonial liquation furnaces of 

 Malbosc, in the department of Ardeche, in France. Fig* 1392 is a ground plan 

 taken at the level of the draught holes g g, fiy. 1393, and of the dotted line E F ; Jiff. 

 1393 is a vertical section through the dotted line A B, of fig. 1392 ; and fig 1394 is a 

 vertical section through the dotted line c D of fig. 1392. In the three figures, the 

 same letters denote like object*, a, b, c, are three grates upon the same level above 

 the floor of the works, 4 feet long, by 10 inches broad; between which are two 



rectangular galleries, d e, which pass trans- 

 versely through the whole furnace, and lie at 

 a level of 12 inches above the ground. They 

 are separated by two walls from the three 

 fire-places. The walls have three openings, 

 / g h, alternately placed for the flames to 

 play through. The ends of these galleries are 

 shut in with iron doors i i, containing peep- 

 holes. In each gallery are two conical cast- 

 iron crucibles k k, into which the eliqmthicf 

 sulphuret of antimony drops. Their height 

 is from 12 to 14 inches; the width of the 

 mouth is 10 inches, that of the bottom is 6, 

 and the thickness four-tenths of an inch. 

 They are coated over with fire-clay, to pre- 

 vent the sulphuret from acting upon them ; and they stand upon cast-iron pedestals 

 with projecting ears, to facilitate their removal from the gallery or platform. Both 

 of these galleries are lined with tiles of fire-clay 1 1, which also serve as supports to 

 the vertical liquation tubes m m, made of the same clay. The tiles are somewhat 

 curved towards the middle, for the purpose of receiving the lower ends of these 

 tubes, and have a small hole at n, through which the liquid sulphuret flows down into 

 the crucible. 



The liquation tubes are conical, the internal diameter at top being 10 inches, at bot- 

 tom 8 ; the length fully 40 inches, and the thickness six-tenths of an inch. They have 

 at their lower ends notches or slits, o, fig. 1394, from 3 to 5 inches long, which look out- 

 wards, to make them accessible from tho front and back part of the furnaces through 



1392 



