xouN HORTUS JAMAICENStv!. All 



a giciit nvjniber of experiments, lie found one process Mliirli (I'.-.r.iur.caU'd ;i ci-iin^j;! 

 Tolour t( tiik and wool, siijJOfior to lliiit given hy cochineal ; lri,.l> c.f v. hicu weiv nia-U? 

 before a Tuimber of tlie principal dyers in and about London, at li;e nuiseiun of u-.i' 

 Ko^-al i?oeiety, invited there for tliat jnirpose. Hc-also fonnd two other proeessv.-, 

 wiuci; jM'dmised, with very little alteration in their nianufac'ujiv, to allbrd the colour- 

 inakini^ d ,cs of scarlet and purple. lj[)on a moderate calculaii^Mi it was found, that lus 

 colour would go further than three times the ijuantity of cOchineal, which he aecoinited 

 for by remarking, that there is a great part of the insect, as its skin, &c. which alYorls 

 lia dye, but that the whole of his process was genuine colour, wiihhttio or no im- 

 purity. 



" Notwithstandinii- the aclvantaues that miirht he dei'i\'eil 'to the nation iVom this 

 gentleman's discovery, lu; met, upon the wh(jle, with very little encoin-agenunt tu 

 prosecute his manufacture further. It was said, that " our conuiieree with .Spain 

 would be liurt by it;" for tliis very reason it ought to have been encouraged. I am u 

 stranger to the annual importation of cochineal from the Sjxiniards, but the qnantky 

 must certainly be very considerable, as it is so largely consumed in our fabrics and me- 

 dical compositions ; but whatever the quantity may be, it is evident that the process 

 dihcove-red by JNir. Uiz gave [jromise of rendernig the imjjortatiijn of that article wholly 

 unnecessary; and as his colour, weight for weight, was found to gotuiiher in dying 

 fabrics, than tljrice the quantity- of c(jchineal, a great saving would be made by the 

 ^ij-ers themselves, and then- fabrics would be atforded at a cheaper rate, all which 

 'makes in favour of the national balance of trade. There is no doubt but the inventor, 

 for a competent reward (of which be is well deserving), would have j)nblKlied the 

 secret of his process ; thousands of acres now waste in .Jamaica might be cultivated with 

 Mhis plant, with little trouble oi" expence 5 and a quantity obtained answerable to the 

 home demand. 



" The fruit of this plant (the opiiiitiaj, eaten when it is ripe, is said to chock fluxes 

 by its mild restringency ; it is also a powerful diuretic, and sometimes imparts a tinge 

 to the urine ; which furnishes a proof that the juice is not always altered with respect 

 tto the principles of its dye, by the animal salts and fluids with which it has to encouBtcr 

 in its secretion through tliu bod\ . 



" Modern discoveries have shewn a chemical method of ordering tlie cochineal dye, 

 so as to retain a very great brilliancy of colour. 



" Drebel, a Dutch chemise, hrst invented the process of obtaining from cochineal, 

 by means of a solution of tin in aqua rcgia, a bright and solid scarlet, exceeding in 

 beauty and lustre any before produced. This, however, -answered only for woollen 

 stuffs. Monsieur Macquer discovered lately the method ofdyin^- silks, and cottons, 

 or linen, in ecpial perfection, by a slight variation in the common |)rocess. He first 

 dipped a piece of silk into a satiirated solution of tin in aqua regia, somewhat weakened 

 by tlie addition of a quantity oi water, so small as to produce no pre -i|)iiati(;ii of the 

 earth or the metal. Having expressed the liquor from the silk, luid afterwards wa-shod 

 it in water, in order to free it from any superfluous part of tne solution, he dipped it 

 into a decoction of tlie cochineal, quickened (as is usual in'the dyeing of woollen cloths) 

 V'iih a small quantity of cream of tartar. The silk immediately took a full bright colour, 

 which resisted all the tests ur proofs usually e.,ip!o3'ed on v\ool. 



" The dyers are therefore, it ajjiK-ars frou this narrative, now possessed of the art 

 of giving tne cochineal Jye a brilliancy, periiaps sjmevviuii I'.ci.ier uj tint jf ta. eaclus 

 ^uice; yet, in aiimauufdcturcs of tins sort, u is cdftaiu, tha the caeaper riiid simpler 



G <r g 2 - the 



