SILK 



ATTACUS 



Eri 



Assam Silk. 



Early 

 Mention. 



Spun. 



Atkinson. 

 Hugon. 



Erownlow. 



Hot Water 

 Injurious. 



Wardle. 



Food- 

 plants. 



Life- 

 history. 



Within Doors. 



Multivoltine. 



Seasons. 

 Stages. 



Crop. 



The textile sold in India under the name " Assam Silk " is almost 

 invariably the produce of the insect here indicated, though of course muga 

 silk is very much more restricted to and characteristic of the valley of 

 Assam. This is the silk with which the poorer people of Assam used 

 formerly to be almost exclusively clad, while the muga silk (which in 

 India is often classed as a special grade of tasar silk) was that (as already 

 mentioned) employed by the middle and upper classes. 



Historic Records. Perhaps the earliest European record of this silk is of the 

 date 1676, when the agent of Port St. George wrote that large quantities were 

 produced in Goraghat. Milburn (Or. Comm., 1813, ii., 244) gives particulars 

 of what may be accepted as the first European transactions. The cocoons, he 

 observes, are remarkably soft and white or yellowish, and the filament so ex- 

 ceedingly delicate as to render it impracticable to wind off the silk ; it is therefore 

 spun like cotton. Roxburgh gives particulars furnished by his correspondents : 

 Atkinson of Jangypur, Glass of Bauglipore, and Creighton of Malda. These 

 names, and the localities with which they are associated, are interesting as 

 forming links that connect the early records. The last-mentioned observer 

 speaks of the worm as reared entirely in the houses of the people. Atkinson 

 refers to his endeavours to reel the cocoons and to his discovery of this being 

 impossible. Hugon and most other authors say the cocoons are softened by 

 being heated in a solution of the ashes of certain plants. They are then 

 opened out by the hand, the chrysalids extracted, the flattened-out cocoons 

 washed, kneaded in the hand, sun-dried, and then crudely drawn out into 

 threads and spun. Brownlow, who half a century later conducted experiments 

 on a large scale, tells us that the cocoons may be softened before being carded by 

 being placed in a solution of cow-dung and water. Most writers mention the 

 circumstance that hot water injures the fibre and that both the carding of the 

 cocoons and the washing of the fabrics should be done, as much as possible, in 

 cold water. Coming to modern times, Sir Thomas Wardle says, "Abandon all 

 idea of reeling eri silk ; the cocoon is too soft, and the fibres mingled together too 

 irregularly, to afford any hope of successful reeling commercially. Produce 

 it on a large scale, comb and spin it and the success is complete." 



Food-plants. The food-plant of this silkworm, as the name of the 

 insect implies, is the castor-oil or palma christi (liicinus com tun nix). 

 There are two forms of that plant grown for this purpose, a green- and a 

 red-coloured. But there are other food-plants, such as Heteropanaw 

 fragrans the keseru of Assam ; Ailanthus excelsa, Coriaritr 

 nepalensis, Gmelina arborea, Jatropha Citrcas, ZantJio.Jci/lum 

 alatuin, and Zizyphus Jujuba. Of these the two first mentioned are 

 by far the most important (see p. 915). 



Life-history. The eri worm is multivoltine and reared, as already 

 observed, entirely within doors. The castor-oil plant in Assam and 

 Eastern Bengal is allowed to grow spontaneously in the rearer's back 

 garden or on any unoccupied land in the neighbourhood, and no attention 

 is paid to it. The tending of the worms goes on all the year round, and is 

 accomplished by the females of the household. As many as eight to 

 twelve broods have been recorded, but those actually reared are about half 

 that number. In fact the autumn, winter and spring broods, or those that 

 spin their cocoons in November, February and May, are most highly 

 valued. The broods of June to September are only reared for the purpose 

 of perpetuating the stock. The stages in the life of the insect are as 

 follows : hatching, 7 to 15 days ; feeding as a worm, 15 to 32 days ; 

 spinning the cocoon, 3 to 6 days ; resting within the cocoon, 15 to 30 days ; 

 and lastly, life as a moth, 3 days. The range indicated is due to the 

 influence of the seasons. 



Crop. Mukerji estimates that from an acre of castor-oil plants it 

 would be possible to obtain from 60 to 90 seers of pierced cocoons a year. 



1012 



