MONTHLY SUMMARY. '577 



staple from one continuous unl)roken thread of from 600 to 1000 

 yards in length, to a multitude of short cut pieces scarcely more 

 than an inch long. This is a necessary consequence of the cocoon 

 being completely spun round and closed in on every side. Some- 

 times the moth cuts its way out at the end of the cocoon, in 

 which case it may be unwound ; but this is rare. When the 

 cocoon has been thus cut up, its value as silk is gone, but it may 

 be worked as cotton ©r other short stapled textile material. 



With the AiLANTHUs Silk- worm it is otherwise. Its chrysalid is 

 contained in a cocoon, with a hole at the upper end, framed like 

 the neck of a bottle, out of which anything from within can make 

 its escape, but nothing from without get in. It is, when closed, 

 like a shaving or bottle brush, opposing a multitude of elastic 

 hairs to whatever seeks to enter; but having an easy passage up 

 the raiddle to the moth when it wishes to come forth. Being 

 thus differently constructed, it is not necessary to destroy the grub 

 to get the silk unwound. The moth may be allowed to escape 

 before attempting this. The cocoon remains as perfect after its 

 escape as before. This is a great advantage, in the saving of 

 moths ; but unfortunately the difference in construction giv^s rise 

 to another difificulty. On putting the empty cocoon into hot 

 water to melt the gum which holds the silk threads together, the 

 water fills the empty cocoon, and it sinks to the bottom, where 

 the weight aud friction at the bottom present a resistance which 

 is not felt with the floating cocoon of the common silk- worm, 

 and breaks the thread. Unless this were remedied, the cocoon .of 

 the Ailanthus worm would be of no more value than the cut 

 cocoon of the common silk-worm ; but in the present dearth of 

 cotton even that is of considerable value. It is carded and 

 treated like floss silk, and, as already mentioned, when so treated, 

 is worth Is. 6d. a pound. Could it be wound up it would then 

 bear the price of silk, which of course is considerably higher. 



It was sufficiently known that this could be done, because fabrics 



made of the Ailanthus silk received from China had been found to 

 have been woven with one continuous thread ; and European in- 

 genuity has now hit upon a plan for accomplishing it. Madame 

 de Cornelian and M, Forgemol have the merit of discovering 

 a method of winding off the raw silk from the cocoons. This 

 process, however, has not yet been introduced into England, 

 but will no doubt speedily be so. When this is done, instead 

 of Is. Gd. per pound, it will yield a considerably higher price. 

 Neither the colour nor the lustre of the Ailanthus silk, however, 



