82 Silks and Silkworms . [February, 
of domestication in China, Bengal, and Burmah, and that 
their silk is not unknown in trade. These are Bombyx textor, 
B. sinensis , B. crcesi , B. fortunatus, and B . Arracanensis. It 
is, however, a great mistake to imagine that the power of 
producing silk in commercial quantities and of useful quality 
is limited to these six species. Two entire families of moths, 
the Bombycidse and the Satufniidse, secrete silk to a much 
larger extent than do other inserts, and amongst these no 
fewer than fifty-seven species have been more or less closely 
studied by Mr. Wardle with a view to their utilisation. The 
produce of these species is known as wild silk, inasmuch as 
the inseCts are not systematically bred in a state of domes- 
tication, and fed upon cut leaves supplied to them regularly, 
but are chiefly collected in the forests. Hence the supply is 
necessarily limited and fluctuating, and the part which these 
silks are capable of playing in the arts has not been till 
lately worthily appreciated. 
It may be asked, What necessity is there for promoting 
the culture of these silks, and for introducing them into 
commerce ? To this question there are three sound answers. 
As the products in question will be, if developed, a source 
of remunerative employment to the people of India, it is a 
matter both of policy and of duty to turn them to the best 
possible account. Again, these silks possess properties in 
some respeCts different from those of common silk, so that 
they suggest novel applications in the decorative arts. 
Lastly, the supply of silk at present is quite unequal to the 
demand. Hence has arisen that disgraceful fraud known as 
“ weighting ” or “ loading.” Silks in these days are not 
dyed for the legitimate purpose of giving them some desired 
colour, but, especially in the case of black goods, of in- 
creasing their weight. The manufacturer when he sends, 
say, ioo lbs. of silk to be dyed, stipulates that he shall re- 
ceive back sometimes as much as 300 lbs., the difference 
being made up by the vegetable and mineral matter depo- 
sited upon the fibre. This procedure has become so general 
that its immoral character is entirely overlooked, and it may 
perhaps excite the anger of the reader if I pronounce it — as 
I am bound to do — fully on a level with forgery and coining. 
In justification of this view I must point out that the value 
of silk is based upon certain physical and chemical proper- 
ties which it naturally possesses. It is a very poor con- 
ductor of heat and of electricity ; it bears a great strain in 
proportion to its thickness, and by reason of its smoothness 
it is less affeCted by friction than are other textile fibres. It 
is, further, not readily combustible, and may be pronounced 
