CHALYBEATE.

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cords in a horizontal direction along the lowest rails of the gallery, whereby ^ "^guniformly besmeared. As soon as the whole web, consisting of about 40 yards, ^ e jcoated with the viscid varnish, it is extended horizontally upon rollers, in thepart of the gallery, and left for a day or two to dry. A second and third coat a ^ ^applied in succession. Two such webs, or pieces, are next cemented face to _ g ’n apassing them, at the instant of their being brought into contact, through be y^ypair of wooden rollers, care being taken by the operator to prevent the formation ^ e d

creases, or twisting of the twofold web. The under one of the two pieces being in thefor the lining, should be a couple of inches broader than the upper one, to ins ^nt-uniform covering of the latter, which is destined to form the outside of the g oB) eSThe double cloth is finally suspended in a well-ventilated stove-room, till it un derdry, and nearly free from smell. The parings cut from the broader edges of t 'pjiepiece, are reserved for cementing the seams of cloaks and other articles of d*? 38 ' jjjngtape-like shreds of the double cloth are in great request among gardeners, tor

up the twigs of wall shrubs.

Mr. Walton, of SowerTby-bridge, has recently substituted sheet Indian ru e sll -leather, in the construction of fillet-cards for the cotton and tow manufactures,perior elasticity of this article is said to prove advantageous in several respects- rubWMr. Charles Keene, proprietor of the extensive and well-organised India ^ cn .factory in Lambeth, obtained a patent in March, 1840, for applying a coa ^ ]))11( leoutcliouc to the outer surface of flexible leather. The varnish of caoutchou ;twith oil of turpentine, has so much lampblack incorporated with it, as to (],er,

to the consistence of dough. The edge of the doe-skin, buck-skin, or W r”dia rob**being introduced between a pair of wetted iron rollers, as much of the Inn c0 vet

compound, softened by a gentle heat, and rolled into a proper length as ^ 31

the leather, is laid in the hollow between the leather and the moist cylm "dry,their rotation, the coating is evenly affected. When the surface has becon ^ pjtlcmay be embossed or gilt, and varnished over with a solution of shellac, "*1 | ca th elVenice turpentine, in alcohol. After two or three applications of this kind, unartiff:is passed through a pair of rollers, either smooth or embossed. When made v'vai' n ' s * 1 lSsuch as shoes or portmanteaus, &.C., are to be covered, the Indian rubbeiused in a thinner state.— Newton’s Journal, xxiii. 357. \Vatc r .

CARMINE. This valuable pigment is often adulterated with starch. ^ jcavit 1 ?ammonia enables us to detect this fraud by dissolving the pure carmine, anthe starchy matter, as well as most other sophisticating substances. > 3UCcarmine is apt to spoil with damp. • oC .

CASSAVA, or Tapioca, is obtained principally from the Jatropha ] e jui< :C .extraction is remarkable for the large quantity of hydrocyanic acid which ^'^jclnthat plant contains. When distilled it affords, as a first product, a liqu° r ^ tcS;the dose of 30 drops, will cause the death of a man in the course of six: min n . eI , e rat e ^it is well known that this acid does not pre-exist in the plant, but that it 13 = j„ \vh°jin it, after it is grated down into a pulp* It would be' interesting to dis c °' r oot, al \-state the substance exists, from which it proceeds. After the grating of th |- or mwashing of the pulp, this is dried upon hot plates, to agglutinate it into l ped r °.concretions, constituting the tapioca of commerce. But the starch of the i ’

floated in water, is spontaneously deposited, and, when dried in the sun, torflour, called moussache by the French . _ „,() SOW

CASTOR OIL. Imported for consumption in 1839, 710,344 lbs.; in * ’

lbs.: duty, Is. 3d. per cwt. . , f

CEMENTS. See Mortar, Hydraulic. . g thor°'of

An excellent cement for resisting moisture is made by incorporating f pal 13 ^eight parts of melted gluq^of the consistence used by carpenters, with p 0 rty' el "ytlinseed oil, boiled into varnish with litharge. This cement hardens in abo tight-

ah° „ ton®

for

hours, and renders the joints of wooden cisterns and casks air and '■ vaie ,„ ^ ao u ' i

compound of glue with one fourth its weight of Venice turpentine, ‘ c ur^> a 0 fserves to cement glass, metal, and wood, to one another. Fresh made cne^ s0 quti 0 ^,jj Cold skim-milk cheese, boiled in water to a slimy consistence, dissolved ,n , ce jain. * n dbicarbonate of potash,-are said to form a good cement for glass and 1 ]0 ‘ ^ floa® ingluten of wheat, well prepared, is also a good cement. White of eggs, w tean ijoi®water well mixed, and smeared over linen cloth, forms a ready lute for s -

out of

con‘»:

small apparatus.

White lead ground upon a slab with linseed oil varnish, and kept ^air, affords a cement capable of repairing fractured bodies of all kinds,few weeks to harden. When stone and iron are to be cemented togctheiol‘equal parts of sulphur with pitch answers very well.' .

CHALYBEATE is the name given in medicine to preparations ^ j s (hemost agreeable, and one of the most powerful, forms of such medicm >

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