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' iinous, and covered with peat mofs : there is but Httle 

 !ieath, but abundance of a rough fort of grafs called lubbo, 

 which grows naturally, and affords tolerable pafture for 

 iheep, liorfes, and black cattle. Though the crops raifed 

 are not fufficient for above eight months' confumption, yet 

 the inhabitants, by the advantage of having plenty of fuel, 

 and catching immenfe quantities of fmall fifh, live comfort- 

 ably, and as well as the generality of the peafants of Scotland. 

 N. lat. 6o<= 56'. W. long. 1° 20'. 



YELL AGOOD, a town of Hindooftan, in Golconda ; 

 45 miles S.E. of Canoul. 



YELLAMOODY, a town of Hindooftan, in the pro- 

 vince of Madura ; 25 miles W. of Madura. 



YELLANG, a town of Burmah ; 14 miles S. of 

 Mellone. 



YELLOOR, a town of Hindooftan, in Baramaul ; 6 

 miles N.N.W. of Namcul. 



YELLOW, a bright colour, reflefting the moft light 

 of any after white. See Colour. 



The word is formed from the Italian glallo, or the Ger- 

 man gsel, which fignifies the fame ; or from the Latin gal- 

 hanus, bright, gay. 



There are divers yellow fubftances that become white, 

 upon wetting and drying them again feveral times in the 

 fun: fuch as wax, hnen cloth, &c. (See Bleaching.) 

 And the fame bodies, if they be already white, and con- 

 tinue a long time in the air without being wetted, turn 

 yellow. 



Paper and ivory, applied near the fire, become fuccef- 

 fively yellow, red, and black. Silk, when turned yellow, 

 is whitened again with the fumes of fulphur. 



Yellow, in Dyeing, is one of the five fimple and mother 

 colours. See Colour. 



The only materials ufed by the calico-printers for the 

 produftion of fine yellows are the quercitron-bark (fee 

 QuERCUs), and the Weld, or Refeda Luttola, which fee. In 

 order to obtain calicoes of the fineft yellow or more delicate 

 lemon colour, it is neceffary to dry the pieces in the open 

 air, as the ftove would not fail to injure fuch colours ; ftove- 

 drying having a tendency to change a yellovi' into an orange. 

 In the operation of dunging the mordants for thefc pale yel- 

 lows, care (hould be taken that it be not done at a higher 

 temperature than 96° or 100°, as fuch a high temperature 

 would impair their beauty. But befides, by dunging at this 

 low temperature, the dyeing may be completed at about 

 110°, which will give a much livelier colour than if a higher 

 temperature had been employed. For all the different 

 fhades of reds and yellows, the mordant employed by calico- 

 printers is the acetate of alumine ; which is prepared by a 

 mixture of the fulphate of alumine with acetate of lead, 

 both in a ftate of folution ; fo that, on the theory of double 

 decompofition, fulphate of lead is formed, which precipi- 

 tates while the acetate of alumine remains in folution. Of 

 late this article has been prepared from the pyroligneous 

 acid, by means of lime and alum, in the following manner : — 

 The pyroligneous acid is firft paffed through a ftill, to diveft 

 it of a portion of the tar which is always diffolved in it : it 

 is then faturated with lime or whiting ; and the acetate of 

 lime thus formed is decompofed by a heated folution of ful- 

 phate of alumine. The refult of this double decompofition 

 is fulphate of lime, which precipitates, and acetate of alu- 

 mine, which is drawn from the fediment of the calcareous 

 fulphate, and preferved for ufe. Mr. Parkes cautions the 

 manufafturer again ft the ufe of lime iu the procefs for mak- 

 ing acetate of alumine ; and he fays that the true mode of 

 making it, though more expenfive, is that recommended by 

 BerthoUet, which confifts in decompofing fulphate of alu- 



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mme by means of faccharura faturni, or acetat- of lead 

 Mr. Parkes mentions a method of producing yellows on 

 calico, which, though not often pradtifed, has neverlhelefs 

 a very good effeft. The procefs is as follows :— A ftronjr 

 decodion of bark, thickenecj with gum tragacanth, is to 

 be mixed with a portion of very pure muriate of tin ; and 

 this, when printed with the ufual management, will produce 

 a colour of great brightnefs and durabihty. This mode 

 poffeffes one very important advantage ; viz. that if it fhould 

 be neceffary to pad a piece in diluted acetate of alumine to 

 obtain a pale lemon ground, the yellow figures previoufly 

 done by the above procefs will not give out any part of 

 their colour to the fecond mordant ; whereas, whenever a 

 ftrong yellow has been produced in the common way, the 

 pattern is very apt to fpread, and to become irregular, and 

 often to ftain the ground, when the piece comes a fecond 

 time into the acetate of alumine. Parkes's Eff. vol. ii. 



Turmeric likewife gives a good yellow, though not the 

 beft. 



Woollen cloth, impregnated with a folution of alum and 

 tartar, acquires on being boiled with the watery decoftion, 

 an elegant, but not very durable orange-yellow or gold- 

 coloured dye. It is rarely made ufe of by the dyers, on 

 account of its price, and the perilhablenefs of its colour. 



There is alfo an Indian wood that gives a yellow colour 

 bordering on gold. This wood, called Jupck, is a fpecies 

 of mulberry-tree, of a deep fulphur-yellow colour, which 

 it readily gives out both to water and fpirit. The watery 

 decoftion dyes prepared woollen of a very durable orange- 

 yellow : the colour is imbibed by the cloth in a moderate 

 warmth, without boiling. 



The fujlet or fiiflel of tlic French is a yellow wood or 

 root, very different from our fuftick : it gives a fine orange 

 dye to woollen, but the colour is extremely perirtiable in the 

 air. This is called cotinus coriaria, or Veniee fumach. 



The leaves of many kinds of herbs and trees give a yellow 

 dye to wool or woollen cloth that has been previoufly boiled 

 with a folution of alum and tartar. There is, indeed, no 

 colour for which we have fuch plenty of materials as for 

 yellow. 



Mr. Hellot obferves, in his Art de Teindre, that all 

 leaves, barks, and roots, which on being chewed difcover 

 a flight aftringency, as the leaves of the almond, peach, 

 and pear trees, afh-bark (efpecially that taken off after the 

 firft rifing of the fap in fpring), the roots of wild patience, 

 &c. (fee Leaf), yield durable yellows, more or lefs beauti- 

 ful, according to the length of time that the boiling is con- 

 tinued, and the proportions of alum and tartar in the pre- 

 paratory liquor : that a large quantity of alum makes thefe 

 yellows approach to the elegant yellow of weld ; that if the 

 tartar is made to prevail, it inchnes them to an orange ; and 

 that if the roots, barks, or leaves, be too long boiled, the 

 yellow proves tarnifhed, and acquires fhades of brown. 

 Neumann's Chemical Works, by Lewis, p. 384. 434. 



The Chinefe are famous for their yellows in dyeing, 

 which never change with wafhing. They make this dye of 

 the flowers of the acacia, in a manner in which we might 

 ufe feveral of our produftions to a great advantage. 



It is thus : they gather the flowers before they are per- 

 feftly ripe, and dry them in an earthen veffel over a gentle 

 heat, till they crifp up in the manner of tea-leaves : they 

 then add to them the ripe feeds of the fame tree in different 

 proportions ; and then boiling them in river water with 

 alum, they give the yellow in any degree that they pleafe. 



They have three kinds of yellow, which they diftingui/h 

 by the names of Ngo-hoang, king-hcang, and hoang alone. 

 The firft of thefe is the brighteft yellow : to dye five or 

 I 2 fix 



