338 FERMENT OILS 



in the proper proportions, the different kinds of fibres intended to form tlio stuff; and 

 then, by the vibratory strokes of the bowstring, to toss them up in the air, and to 

 cause them to fall as irregularly as possible, upon the table, opened, spread, and 

 scattered. The workman covers this layer of loose flocks with a piece of thick 

 blanket stuff slightly moistened; he presses it with his hands, moving the lisiirs 

 backwards and forwards in all directions. Thus the different fibres get interlaced, by 

 their ends pursuing ever tortuous paths ; their vermicular motion being always, how- 

 ever, root foremost. As the matting gets denser, the hand pressure should bo in- 

 creased, in order to overcome the increasing resistance to the decussation. 



A first thin sheet of soft spongy felt being now formed, a second is condensed upon 

 it in like manner, and then a third, till the requisite strength and thickness bo ob- 

 tained. These different pieces are successively brought together, disposed in a way 

 suitable to the wished-for article, and united by continued dexterous pressure. The felt 

 must bo next subjected to the fulling mill. See HAT MANUFACTURE, and KAMPTTTLICON. 



FENXS. The refuse of whale blubber. It is used as a manure, and has been 

 employed in the manufacture of Prussian blue. 



FETCNEIt. The Ancthum Faniculum, a plant yielding an aromatic oil. The leaves 

 are used for making sauce ; the seeds are carminative. 



FENUGREEK. The Trigonella Foennm-Gracum, an herb cultivated throughout 

 Greece and the East as an article of food. The seeds, which alone arc used, are 

 oaten, both boiled and raw, mixed with honey. The Trigonella c&rulea is a native 

 of Switzerland and Bohemia. The flowers are of a delicate blue colour, and have an 

 odour like that of Balsam of Peru. This odour increases by drying, and the Italian 

 perfumers use it extensively. The Swiss use it to flavour some of their cheeses. 



FER ACIEREUX. Steely iron produced by the Catalan process. See IRON. 



FERMENT (Eng. and Fr. ; Hefc, Ger.) is the substance which, when added 

 in a small quantity to vegetable or animal fluids, tends to excite those intestine motions, 

 or changes, which accompany fermentation. It seems to bo the result of an alteration 

 which vegetable albumen and gluten undergo with contact of air amidst a fermenting 

 mass. The precipitates or lees which fall down, when fermentation is finished, consist 

 of a mixture of the fermenting principle with the insoluble matters contained in the 

 fermented liquor, some of which, like Jiordeine, existed in the worts, and others are 

 probably generated at the time. 



To prepare a pure ferment, or at least a compound rich in that principle, the pre- 

 cipitate separated during the fermentation of a clear infusion of malt, commonly called 

 yeast or barm, is made use of. This pasty matter must be washed in cold distilled 

 water, drained and squeezed between the folds of blotting-paper. By this treatment 

 it becomes a pulverulent mass, composed of small transparent grains, yellowish grey 

 when viewed in the compound microscope. It contains much water, and is therefore 

 soft, like moist gluten and albumen. When dried it becomes, like these bodies, 

 translucid, yellowish brown, horny, hard, and brittle. In the soft humid state it is 

 insipid, inodorous, insoluble in water and alcohol. If in this state the ferment be 

 loft to itself, at a temperature of from 60 to 70 F., but not in too dry a situation, it 

 putrefies with the same phenomena as vegetable gluten and albumen, and leaves, like 

 them, a residuum resembling old cheese. See FERMENTATION and YEAST. 



OIIsS. Volatile oils produced by the fermentation of plants, and 



not originally contained in them. These wore the quintessences of the alchemists. In 

 most cases they are obtained by placing the loaves of the flowering plant in water, 

 and allowing them to ferment; after which the liquid is distilled, and the ferment 

 oil usually separated by means of ether. The following ferment oils are described 

 in Watts's 'Dictionary of Chemistry' : 



Ferment oil of Chterophyllum sylvestre. Wild Chervil. Common parsley. 



Chelidonium majus. The larger celandine. 



Conium maculatum. Common hemlock. 



Errythrcea ccntuarium. Little centuary. 



Echium vulgarc. Vipers' bugloss. 



Erica vnhjaris. Common heath. 



Marrubium vitlytarc. White horohound. 



Achillea millefolium. Common yarrow. 



., Plantago. The plantain. 



Quercus roliur. Oak. 



Salix pcntan( l.ra . The willow. 



Salvia pratensi*. Meadow sago. 



Trifolinm fibrin urn. The clover. 



,, Tussilago farfara. Colt's foot. 



Vitis vinifera. The vino. 



Urtica vrcvx. The nettle, 



Diseased apples. 



