VENTILATION.
1277
With^" 0 ^’ °' m l °f wa ^ m ^ s > ' s extracted by expression; and that which is extractede x „ ? u . 1 heat, is certainly the most pale, pure, and mjtrilive seasoning, and retains anp| e * l . s * te taste of the fruit. That designed for the arts is of inferior quality, and isto p 1 imported to us from France ; the heat it undergoes in its torrefaction, previousV s ex Pression, disposes it to dry more quickly than that expressed by the cold process ;c 0 jg r at the same time, the heat, though it frees it from its unctuous quality, gives it morea s j-‘ When it has been extracted by the cold process, it may be prepared in the same way*° r l * le P°PPy.°d-
*'i«ti> i at)ov e article I have retained the workmen’s names—gum, white vitriol, &c.,VFr»°f res 'n, sulphate of zinc, &c.
Witl^NS ( Filons , Fr.; Gauge , Germ.), are the fissures or rents in rocks, which are filledyJI ec| diar mineral substances, most commonly metallic ores.
N STONES, or GANGUES , are the mineral substances which accompany, and fre-VpT enc ' ose > We metallic ores.ypi-LUM, is a fine sort of Parchment , which see.pl a f J ' ET (py 0!tr<; p r _. Sam/net, Germ.), a peculiar stuff, the nature of which is ex*Yp,".Under Fustian and Textile Fabrics.
YpjJCS, is the mythological name of copper.
to PILATION, or the renewal of fresh air in stagnant places, is nowhere exhibitedTentage as in the coal mines of Northumberland and Durham , where5 * r 'th U, l ^ e bas carried well nigh to systematic perfection the plan of coursing theSp^jWugh the winding galleries, originally contrived about the year 1760, by Mr. Jamesdie .."'g, Workington, the ablest pitman of his day." He converted the whole ofthen* , SSa §es into air-pipes, so to speak, drew the current of air from the downcast pit,' v ° r ki raversec l d U P und down, and round about, through the several sheaths of the
111- l?S. Cn flint «n nnrllniilnr rrnlloeif Ilf n n InfV nrifhnnt n ntlTi-ont r\(* air H"p
th,
s j so that no particular gallery was left without a current of air. HeUei Uoh^ s ucceeded in actually expelling the noxious gases from the mines; thoseMth • ’ w Mch in Germany , at no remote era, were wont to be combated by the priestst>rov e lII1 Potent exorcisms or pious frauds. Before Mr. Buddie introduced his im-Ln» ? ents > he has known the air to be led through a series of workings, thirty milese *ore it made its exit. There is in every coal mine an experienced corps, called0| >ce p n ’ because they travel over the waste, or the exhausted regions, who can tell at^ 0 °tV whistling sound which the air makes at the crevices in certain partitions andhe»;’Whether the ventilation be in good condition or not. They hear these stoppingskby f : ° f} n S or call, as they say, whenever an interruption takes place in any point of the)>ea V y p an hne. Another indication of something being wrong, is when the doors get so1|,s tant ,aat ’■he boys in attendance upon them find them difficult to shut or open. The''’ton,, Suc h a defect is discovered by any one, he cries aloud, “ Holloa, there is something
ion„ a ueiect is aiscoveri
fq doors are calling !”
ta refyj ' ^bedding's system, the whole of the return air came in one current to hisfurnace (see letter c,fig. 1158), whether it was at the explosive point or not.kep l • lslc ibution was often fraught with such danger, that a torrent of water had to be^then rea< Hucss, under the name of the waterfall, to be let down to extinguish the fire in at,l| ' 0 a O [ 1 t ‘ Many explosions at that time occurred, from the furnaces below, and also down■ Abn, lu bes from the furnaces above-ground.
““Port the year 1807, Mr. Buddie had his attention intensely occupied with this mostl hro,,„ ant object, and then devised his plan of a divided current, carrying that portion°f the rt - lhe active furnace c, fig. 1158, and the portion of the air from the foul workingsbp th* 1 ; which, descending in the downcast pit A, coursed through the clean workings,Utepi baud' furnace d, till it reached a certain elevation in b, the upcast pit, above the’l*oi )1 >L. e ' The pitmen had a great aversion, however, at first, to adopt this plan, as theythey 5 *uat the current of air, by being split, would lose its ventilating power; butore long, convinced by Mr. Buddie to the contrary. He divides the maina?\ir e . 'a*- 0 two separate streams, at the bottoin of the pit A, as shown by darts in thec Ptr en ’ d' e feathered ones, representing that part of the pit in which the course of the°f ca r v ° air is free from explosive mixture, or does .not contain above one thirtieth"Pliej ? rete d hydrogen, as indicated by its effect upon the flame of a candle. Thef°int ) j s a , rls denote the portions of the mine where the air, being charged to the firingstl aft’ on, 'i °d towards D, the dumb furnace, which communicates with the hot upcast; °f reach of the flame, and thence derives its power of draught. By suitable alter-Work' st °PP>n?s (see the various transverse lines, and the crosses), any portion of
rrifltr iv»r Oironnv nf thp flirnapp. hplohl ^ Wntrlit within, t]
.may, by the agency of the furnace, belaid out of, or brought within, the
.may, b, _.. 0 _ „ , ___. 7 _ a
vitiated current, at the pleasure of the skilful mine viewer; so that, if he
'"’taiCU CUlieillj <**■ V- in me SHlliUt ilJIIie VIcWCl i w w
;i Med necess ary, he could confine, by proper arrangements if his furnace, all theMi ni Urre nt to a mere gas-pips or drift, and direct it wholly :hrough the dumb fur-^ PIl gineer8 use the term good pitman , as admirals do good seaoian, * denote a proficient in h;s