Dec. 1, 1864.] THE TECHNOLOGIST. 



RESTORATION OP THE SILKWORM. 223 



sent to him by Sir. Cope, of Umritsir, were inferior in size, and far more 

 irregular in form, than those sent by me from Mussooree, where the 

 climate is better adapted to the species. The fact is moreover fully estab- 

 lished by the annual loss sustained by Jaffer Ali as above narrated, as 

 well as by Mr. Cope's expressed intention of sending his Punjab-bred 

 eggs to the hills during summer, and of importing annually fresh 

 seed from Cashmere. The same remark is equally applicable to 

 Oudh. 



That the thinness of the leaf, both in M. multicaulis and M. cucullata, 

 is a very serious defect may be gathered from Count Dandolo's remark, 

 that " the less nutritive substance the leaf contains, the more leaves 

 must the silkworm consume to complete its deA r elopment. The result 

 must, therefore, be that the silkworm which consumes a large quantity 

 of leaves that are not nutritive, must be more fatigued and more liable to 

 disease than the silkworm that eats a smaller proportion of nutritive 

 leaves. The same may be said of those leaves which, containing a 

 sufficiency of nutritive matter, contain little resinous substance ; in that 

 case the insects would thrive and grow, but probably woidd not produce 

 either a thick or strong cocoon proportionate to the weight of the silk- 

 worm, as sometimes occurs in unfavourable seasons. My experiments," 

 continues the Count, " prove in the ultimate analysis that, all things 

 balanced, the qualities of the soil produce but a very slight difference 

 on the quality of the leaf ; that which will appear most evident is, that 

 the principal influential cause of the fineness of the silk is the degree 

 of temperature in which the silkworm is reared. It is neither the water 

 nor the fibre of the leaf which nourishes the silkworm and renders the 

 cocoon heavy, but the resinous and saccharine substances." 



The concluding sentence, however, is scarcely to be relied on, since 

 the worm in its growth is undoubtedly nourished by the water and the 

 fibre of the leaf, although it is equally true that the weight and thick- 

 ness of the cocoon depend upon the presence of the other substances, 

 while it is necessary to guard against the error of endeavouring to pro- 

 duce too much fineness in the silk, since I have already shown that to 

 be an indication of too high a temperature and of the consequent 

 degeneracy of the worm. Besides which, that the soil must in some 

 measure act upon the quality of the leaf can scarcely be doubted when 

 we consider that it is from the soil that the tree derives its nourishment, 

 and the changes which occur both in the shape and substance of the 

 leaf and in the colour of the fruit can be attributed, I imagine, to 

 nothing else. 



In regard to the treatment of the trees, it has been justly remarked 

 that they may be very seriously injured by too close plucking; it has 

 been forgotten, however, by those who in India have laid some stress 

 upon the fact, that the remark applies rather to the mulberry-trees of 

 Europe and other temperate climes, than to those of tropical regions ; 

 for in the former there is too short a summer to enable the tree to pro- 



