90 ANNUAL OF SCIENTIFIC DISCOVERY. 



tially evaporated, and the stiff paste or dry powder pressed into a solid 

 mass in the dies or mould, which have been previously heated to about 230 

 or 280 3 Fahrenheit; after being so solidified they are polished in the ordi- 

 nary manner of polishing ivory. Instead of using ivory dust, steamed and 

 finely powdered bones, porcelain, cotton, and various finely powdered mate- 

 rials may be employed, and the colors may be varied according to the tint or 

 shade required; the ivory or other dust may be dyed similar to cotton cloth. 

 Gum dammar, copal, mastic (and if great elasticity is required, bleached In- 

 dia-rubber or gutta-percha), answer the purpose very well, either with or 

 without shellac ; bees-wax, camphor, and turpentine, are good for some of the 

 purposes, and, according to the ingredients used, it will be perceived that the 

 preparation must undergo various modifications during the process of man- 

 ufacture. 



MACHINE FOR BURKING WOOL. 



Thomas Musgrave, of Northampton, Mass., has invented a machine for 

 removing burrs and dirt from wool, which promises to accomplish the same 

 results with that staple that the gin has with cotton. The machine is very 

 simple, and is in the form of an attachment to the ordinary carding machine. 

 It adds only fifteen or seventeen dollars extra expense to the carder. The 

 value of it will be obvious to all who know how foul the South Ameri- 

 ican wools are with burrs, and how great is the expense of cleaning it by 

 any process hitherto known. After being washed, the wool is placed 

 upon the apron of Mr. Musgrave's machine, and carried by it to two roll- 

 ers, covered with coarse cards, lying parallel and revolving inwards. As 

 the wool passes these it meets the " burrer," a cylinder of about six inches 

 in diameter, composed of steel rings slid upon a shaft. The circumfer- 

 ence of each ring is cut into teeth something like those of a cross-cut saw; 

 between each of the rings is a circular wire to separate them. The whole are 

 then driven together, forming a cylinder, of which the surface is composed 

 of these steel teeth, of which there are eleven to the inch. As the wool 

 passes the feeding rollers it is caught by the teeth ; the wool itself is drawn 

 into the space between the teeth, leaving the burr on the surface. Above 

 this cylinder is another of wood, into which are fixed longitudinally spiral 

 blades. This revolves so as nearly to touch the under cylinder, but in a con- 

 trary direction. Thus it is obvious that the burrs on the under cylinder 

 coming in contact with the blades of the upper one, are cut off. They are 

 received upon an apron, which removes them. In the ordinary manner the 

 wool freed from the burrs is then delivered to the carding machine. Were 

 the burrs large and hard, like cotton seed, no more would be required; but 

 the small, brittle burrs of the South American wool are apt to be broken, and 

 the fragments get ultimately into the yarn and injure the cloth. To obviate 

 this, Mr. Musgrave has introduced a carding cylinder to take the wool from 

 the first " burrer " and deliver it, better distributed, to a finer one, where the 

 teeth are fourteen to the inch instead of eleven. By this means the wool 

 passes to the carder entirely free from burrs. The thorough mode of its ac- 

 tion may be illustrated by the fact that Mestiza wool Avas passed through, 

 and in a few moments freed from forty per cent, weight of burrs without any 

 apparent injury to the fibre, adding at least fifteen cents per pound to the 

 value of the wool. 



