208

PEARLS, ARTIFICIAL.

the third portion of its working surface into action upon the cross head, the roll will heraised, in order to clear the pulp from knots and other imperfections, and thus completethe operation of the engine. In order to raise the cross head and roll to the heightfrom which it descended without loss of time, or to lift the cross-head entirely from onthe cam when requisite ; a lever 2, or other suitable contrivance may be attached to theapparatus, also a shaft may be passed across the rag-engine, and both ends of the roll majbe raised instead of one only, as above described.

The patentee does not claim as his invention the lowering and raising the roll of therag engine, nor the lowering of it by mechanism, as this was effected in Mr. Amosespatent of 1840; but he claims the above peculiar apparatus for this purpose .—Ncicton iJournal, xxiii. 254. C. S.

PAPER— Gross produce of revenue from. In 1831, 723,2481.; 1836,812,7821.; 1837,555,9431.; 1840, 626,6631.

PAPER CLOTH. The preparation of this fabric is thus described in the spec 1 'fication of Mr. Henry Chapman’s patent of January, 1843. A suitable quantity °‘canvass, gauze, muslin, calico, linen, &c., is wound upon a roller, which is introducebetween the third press felt of a Fourdrinicr paper machine; and between the aboveroller and the endless felt a trough is introduced, containing a solution of gum, gl ue >&c., with a roller partially immersed in it. Pulp being now allowed to flow upon thendless wire wheel of the machine, paper is made in the ordinary way; and when thendless sheet of paper has been led through the machine, the end of the cloth is brgughover the upper part of the roller in the trough, and moved onward in the direction thpaper is proceeding. The motion of the cloth causes the roller to revolve, and the ahesive material carried upon its surface is imparted to the cloth, which is then laid up 0 "the paper, as it passes over the roller immediately preceding the third or last P resS ,roller. By passing between these rollers, the cloth and paper are firmly united, a ®being dried by the steam cylinders, form the compound fabric. If required, a P a P ..surface may be applied to the other side of the cloth, by repeating the operation.the cloth be dressed with strong starch, the bath of adhesive solution may be dispensewith. The following prescription is given for making that solution :— s

Dissolve in 15 parts of water, 4 of soda, and combine with this solution, by ® ea (of heat, 9 parts of yellow rosin; boil for an hour, adding a little linseed oil to P reve efrothing, and add 1 part of glue to the mixture; after which dilute the whole with oand a half times its weight of water, and strain through flannel. Thirty parts of 1 "composition are to be mixed with one part of flour-paste, and six parts of paper-P” 11 ’which mixture is to be used warm. „

PEARLS, ARTIFICIAL, and BEADS, The material out of which these aformed are small glass tubes like those with which thermometers are made. The tu ‘for the bright red pearls consist of two layers of glass, a white opaque one inter 11 ®. nand a red one externally; drawn from a ball of white enamel, coated in the Bohe» ^method with ruby-colored glass, either by dipping the white ball into a pot °* g {glass, and thus coating it, or by introducing the ball of the former into a cylindethe latter glass, and then cementing them so soundly together as to prevent ^separation in the subsequent pearl processes. These tubes are drawn in a g a B^!X eS cthe glasshouse to 100 paces in length, and cut into pieces about a foot long. 1 c .are afterward subdivided into cylindric portions of equal length and diameter, 1 yparatory to giving them the spheroidal form. From 60 to 80 together ar ® c( .horizontally in a row upon a sharp edge, and then cut quickly and dexterously at j n rby drawing a knife over them. The broken fragments are separated from thepieces by a sieve. These cylinder portions are rounded into the pearl shape by jjjnsrthem by a suitable heat, and stirring them all the time. To prevent them from s _ VTItogether, a mixture of gypsum and plumbago, or of ground clay and charcoal, is ’in among them. ; g a

Fig-i. 114, 115, represent a new apparatus for rounding the beads; fig- 11 ^„ ur e ;front view of the whole; fig. 115, is a section through the middle of the former o ;;;in the course of its operation. The brick furnace, strengthened with iron ban >

5, 7, 8, has in its interior (see fig. 115), a nearly egg-shaped space B, provi oS jtethe following openings : beneath is the fire-hearth, c, with a round mouth, an ’ 0 p e n-are the smoke flue and chimney, d ; in the slanting front of the furnace is a ^\ c hing, E, fig- 114. Beneath are two smaller oblong rectangular orifices, F, jj wo0 dextend somewhat obliquely into the laboratory, n. it serves for introducinginto the fireplace. All these four openings are, as shown in fig- 114> secu ; eC e, r 'injury by iron mouth-pieces. The wood is burned upon an iron or clay bottom^.^ a tA semi-circular cover, n, closes during the operation the large opening, E, a

other times remains open. By means of a hook, m, and a chain, which res eve r, B,hollow arch, h, the cover, N, is connected with the front end of the long iron ' weigh 1 ’A prop supports at once the turning axis of this lever and the catch, ft, c,