DIRECT BENEFITS DERIVED FROM INSECTS. 219 



said to have been of late years successfully introduced into Spain and the 

 new French colony of Algiers, and now exist both in the stores of the 

 Jardin des Plantes at Paris, and in those of King Leopold at Claremont.^ 



Lac is the produce of an insect formerly supposed to be a kind of ant 

 or bee^ but now ascertained to be a species of Coccus ; and it is collected 

 from various trees in India, where it is found so abundantly, that, were 

 the consumption ten times greater than it is, it could be readily supplied. 

 Tliis substance is made use of in that country in the manufacture of 

 beads, rings, and other female ornaments. Mixed with sand it forms 

 grindstones; and added to lamp or ivory black, being first dissolved in 

 water with the addition of a little borax, it composes an ink not easily 

 acted upon when dry by damp or water. In this country, where it is 

 distinguished by the name stick-lac, when in its native state, unseparaled 

 from the twigs to which it adheres ; seed-lac, when separated, pounded, 

 and the greater part of the coloring matter extracted by water ; lump-lac, 

 when melted and made into cakes; and shell-lac, when strained and 

 formed into transparent laminae ; it has hitherto been chiefly employed in 

 the composition of varnishes, japanned ware, and sealing-wax : but for 

 several years past it has been applied to a still more important purpose, 

 originally suggested by Dr. Roxburgh — that of a substitute for cochineal 

 in dyeing scarlet. The first preparations from it with this view were 

 made in consequence of a hint from Dr. Bancroft, and large quantities 

 of a substance termed lac-lake, consisting of the coloring matter of stick- 

 lac precipitated from an alkaline lixivium by alum, were manufactured at 

 Calcutta and sent to this country, where at first the consumption was so 

 considerable, that in the three years previous to 1810, Dr. Bancroft states 

 that the sales of it at the India House equalled in point of coloring matter 

 half a million of pounds weight of cochineal. More recently, however, 

 a new preparation of lac color, under the name of lac-dye, has been 

 imported from India, which has been substituted for the lac-lake, and with 

 such advantage, that the East India Company are said to have saved in a 

 few months 14,000/. in the purchase of scarlet cloths dyed with this color 

 and cochineal conjointly, and without any inferiority in the color obtained.^ 



Some other insects besides the Cocci afford dyes. Reaumur tells us, 

 that in the Levant, Persia, and China, they use the galls of a particular 

 species of Aphis for dyeing silk crimson, which he thinks might lead us to 

 try experiments with those of our own country.^ That dyes might be 

 thus obtained seems probable from an observation of Linne's, in his Lap- 

 land Tour, upon the galls produced by Aphis pini on the extremities of 

 the leaves of the spruce-fir, which, he informs us, when arrived at maturity, 

 burst asunder, and discharge an orange-colored powder which stains the 

 clothes^; and Mr. Sheppard confirms this observation, the galls of this 

 Aphis abounding upon fir trees in his garden. In fact, we are told that 

 Tenninalia citrina, a tree common in India, yields a species of gall, the 

 product of an insect, which is sold in every market, being one of the 

 most useful dyeing drugs known to the natives, who dye their best and 

 most durable yellow with it.*^ A species of mite {Tromhidium tinctoriuni), 



' Trans. Ent. Snc. Land. iii. proc. ix. * Lesser, L. ii. 165. 



2 Bancroft on Permanent Colors, ii. 20. 49. ■• Reaum. iii. Preface, xxxi. 



* Lack. Lapp. i. 25S. « Trans, of the Sjc. of Arts,'xun. 411. 



