360 FIBROUS RESIDUES 



in hot water ; steep .five to ten minutes in water at 50 to 60 C., containing 2 per 

 cent, sulphuric acid, and wash again. In the meantime prepare the colour-bath by 

 dissolving a few decigrammes of magenta in 28 to 30 cubic centimeters of water ; heat 

 to boiling, and during ebullition add to it, drop by drop, caustic soda till a pale rose 

 colour only remains in the liquid ; take off the fire, and put in the sample ; after some 

 minutes take out to dry. Silk and wool are dyed while the vegetable fibres remain 

 colourless. Wool may be detected in silk by the presence of sulphur : if it is immersed 

 for a short time in plumbate of soda, the silk will bo colourless and the wool black. 

 Or a piece of the tissue, two centimeters square, may be boiled in 10 to 12 cubic centi- 

 meters of Schweitzer's test : in five to ten minutes the silk will be dissolved. If the 

 silk is black add double the volume of Schweitzer's test, and soak ten to twelve 

 minutes ; after taking out the undissolved wool the liquid, quickly neutralised with 

 nitric acid, gives no precipitate if silk is only present, but cellulose is precipitated.' 



FIBRIN 1 . Eecent researches have shown that the substance known as animal 

 fibrin is formed by the union of two distinct albuminous principles, termed, by A. 

 Schmidt, the fibroplastic and fibrinogcnous substances. Fibrin may be obtained in a 

 pure state by agitating or beating new-drawn blood with a bundle of twigs, when it 

 will attach itself to them in long reddish filaments, which may be deprived of colour 

 by working them with the hands under a streamlet of cold water, and afterwards freed 

 from any adhering grease by digestion in alcohol or ether. 



Fibrin, thus obtained, is solid, white, flexible, slightly elastic, insipid, inodorous, 

 denser than water, but containing iths of its weight of it, and without action on 

 litmus. When dried, it becomes semi-transparent, yellowish, stiff, and brittle : water 

 restores its softness and flexibility. 100 parts of fibrin consist of 53*36 carbon, 19*08 

 oxygen, 7*02 hydrogen, and 19'31 nitrogen. As the basis of flesh, it is a very nu- 

 tritious substance, and is essential to the sustenance of carnivorous animals. 



FIBRIN, VEGETABLE. A nitrogenous substance very similar to animal fibrin. It 

 occurs in the gluten prepared from wheaten flour, and in most kinds of grain. 



FIBRO&ITX*. A silicate of alumina occurring in fibrous or columnar forms, 

 associated with corundum, in the Carnatic. Many of the pre-historic stone celts found 

 in Switzerland, France, and the Channel Islands, are said to be wrought in fib- 

 rolite. 



FIBROUS RESIDUES. New Process for separating the Animal from the Vegetable 

 Ingredients. Mr. F. 0. Ward was an exhibitor in 1862 of this process, which 

 received the high approval 01 the jury of Class II., to whose attention it was espe- 

 cially directed. Mr. Ward has been associated with Captain Wynants in carrying 

 out this interesting and useful discovery. These gentlemen placed in the hands of 

 Dr. Hofmann a concise description of their process, which we give in Mr. Ward's 

 words : 



' There is a class of rags of intermediate character, neither wholly composed of 

 vegetal matter, nor exclusively of animal origin. I allude to the residue of fabrics 

 containing both these classes of materials interwoven. 



' Such are the rags of so-called union fabrics, wool and cotton ; of the silk and 

 alpacas woven with a cotton warp ; and of the numerous varieties of stuffs, merinos, 

 &c., which are more and more extensively manufactured every year. Such also are 

 the rags known technically as " seams ; " being the clippings which fall from woollen 

 rags under the scissors of the sorters, who prepare them for the machine by which 

 they are torn into " rag-wool." These pieces are cut off and withheld from the tearing 

 machine, precisely because they have a sewing thread running along them, or por- 

 tions of cotton lining adherent, or other vegetal admixture. In rags of this class, 

 each of the materials present interferes with the use, and diminishes the value, of the 

 other. The paper-maker cannot advantageously work off the cotton because of the 

 wool, which would sprinkle his sheets with coloured specks. The rag-wool manu- 

 facturer, on the other hand, cannot advantageously convert the wool to his purpose 

 because of the cotton, which would show amidst the wool when dyed, as filaments of 

 paler hue. 



' To meet this difficulty two plans have been of late years proposed, viz., the dis- 

 integration of the cotton by means of dilute .acid, in order to the separate recovery of 

 the wool; and the dissolution of the wool by means of caustic alkali, in order to the 

 separate recovery of the cotton. 



' Both these plans, it will be observed, involve the sacrifice of one material for the 

 recovery of the other; for its recovery in the case of the wool, much impaired in 

 strength by acidulation : in the case of the cotton at a considerable expenditure of 

 the alkaline solvent. 



'The process now under review was devised in the year 1857, with special r.f, r- 

 ence to this class of mixed rags; a? also to the unsortable residuum whicli remains 

 under the name of " land rags," after the sorting of a heap has boon pushed as far as 



