334 
THE ART OF REARING 
Cocoons of the Calcined Worms without Stain*. 
ozs. 
1000 ounces of these cocoons contain in chrysalis, 
dried worm or mummy, and envelopes of dry 
saline substance .... 642 
Pure cocoon ..... 353 
Total . . 1000 
The proportion between the weight of the 
mummy and the pure empty cocoon is 18 to 10. 
Seven pounds and a half, that is to say, 
120 ounces of these cocoons, contain about 44 
ounces of pure cocoon. 
As these cocoons are not stained, and yield 
about 12 ounces of spun-silk, out of 21 ounces 
of pure cocoon, it is evident that fi-om 500 ounces 
of pure cocoon may be drawn, — 
OZS. 
In spun silk about . . . 2S§ 
In coarse floss or other substances . 21| 
Total . . 50 
If the spinner only obtains twelve ounces of 
silk from of the healthy chrysalides, while he 
can get twenty-five ounces from the same weight 
of calcined unspotted cocoon ; in buying these, 
there are thirteen ounces more of silk in the of 
* I should think the author meant the white comfit chry- 
salis (dragees), or calcined cocoon. — Translator. 
