50 MECHANICAL FUNCTIONS. 



nothing to fear from them, astronomy was hailed as the 

 noolest and most useful of sciences on this very account ; 

 and yet astronomy in that instance did nothing more for 

 the world than entomology has done in the case be- 

 fore us. 



132. Tusseh Silk-Worm. Before we leave the lepi- 

 dopterous insects, we will describe a species of silk worm 

 found in India, which, although it is not domesticated like 

 the common one of Europe and America, the bombyx 

 mori, still appears from time immemorial to have furnish- 

 ed the natives with an abundance of an inferior kind of 

 silk for common uses. It is called the Tusseh silk-worm, 

 and is found in abundance in many parts of Bengal and 

 the adjoining provinces, and the cocoons are reeled and 

 wove into a coarse, dark-colored, but most durable fabric, 

 called Tusseh dootheis, much worn by the bramins, and 

 other classes of Hindoos. 



133. This silk-worm, whether from want of skill, or 

 from the wild habits of the moths, is unknown, has never 

 been reared in the usual manner of other worms ; the na- 

 tives, therefore, every year, at the proper time, go into the 

 jungles and find the young worms on the limbs of certain 

 trees, W T hich they cut off and convey to other trees of the 

 same kinds near their habitations. These are known by 

 the native names of asseen and byers trees, and these 

 trees are guarded day and night, in order to prevent 

 birds and bats from destroying the young caterpillars. In 

 two or three weeks, these worms acquire nearly their 

 full size, being monsters of four inches in length, and 

 three in circumference ; their colors are of a light green, 

 with a yellowish stripe on each side, the sixth and 

 seventh rings being marked with an oblong golden spot. 

 From the back issue a few long, coarse, distinct hairs, 

 with others of a smaller size scattered over the body, 

 Fig. 37. 



134. When these worms are ready to spin their 

 cocoons in which they change to the chrysalis state, they 

 begin by attaching glutinous filaments to a leaf as a found- 

 ation, and afterward spin a strong cord by which the fu- 

 ture cocoon is suspended to a twig for additional security. 

 The cocoon is of an oval form and firm texture, as rep- 



