SILK. 177 



ing this species. In Yucatan a wild moth lias also been met with, some- 

 what allied to the mulberry worm, which produces silk of a bluish tint, but 

 the gum which envelops it is difficult to remove. 



" Mr. John Maclntyre, a recent traveller in Manchuria, records having 

 met with several new species of silkworm, which he describes in the 

 Chinese Times. One wild worm feeds on the Pinus chinensis. It forms 

 handsome cocoons, which yield a strong silk, but they are so mixed up 

 with the needle-like leaves of the pine, that the winding of the silk 

 would be difficult. On the walnuts he found another, which forms a 

 reticulated cocoon, like a Chinese lantern. He also met with two other 

 species of mulberry worms, one very hardy, which could be fed on 

 lettuce or dandelion leaves, and remains stationary, the other which 

 moves easily from branch to branch in search of food. The rearing of 

 Attacus orizaba of Mexico is to be attempted in France." 



Schappe Silk This is known also as spun silk. In the operation of 

 reeling the silk from the cocoon there is often some that has become 

 disarranged or entangled in such a manner as to prevent its being 

 reeled in the ordinary way. In some cocoons, where the cultivation 

 of silk is carried on extensively, the moth is allowed to emerge, for 

 the purpose of promoting a good breed or reproduction of silkworms 

 at a later stage of the industry. The cocoons from which the moth 

 emerges have their threads displaced. This silk is collected with the 

 waste obtained from the various processes, such as winding, twisting, 

 etc. This waste material is utilised for weaving fringes and for the 

 production of sewing silks of remarkable lustre. 



Tram and Organzine. The above terms are generally adopted to- 

 indicate the longitudinal and transverse threads of silk that are used 

 to build up the structure of a woven fabric. A union cloth of cotton 

 and silk, where the former is the warp and the latter the weft, as 

 in a Barathea cloth, would have a backbone of cotton, and a floating 

 and intersecting tram or weft, that would give a glossy effect to the 

 fabric. 



Tram is composed of one or more single threads free from twist^ 

 that are united in one operation ; later, they are twisted together and 

 form an individual solid thread known as tram silk. 



The fibres of organzine become the potent factors of strength in 

 the warp of the silk woven fabric. Several threads are individually 

 twisted in one direction, after which they are doubled and retwisted. 

 The twist imparted to the yarn or organzine adds strength to the 

 fabric, but an excess of twist is a disadvantage ; it reduces the glossi- 

 ness or lucidity, and the selling price of the silk material is affected 

 prejudicially. As the orgauzine or warp threads have to withstand 



12 



