Polytechnic Association Peoceedings, 685 



Mr. J. K. Fisher said that bringing iron into the fibrous state 

 does not add to its strength. He regarded this common assertion 

 as a fallacy. 



HOW PAPER IS ]VIADE IN CHINA. 



Most of the paper used in China is made from the bark of vari- 

 ous trees and plants, and from the bamboo. The manufacture of 

 bamboo paper is carried on extensively in the southern part of the 

 country. In selecting stock from the bamboo plantations on the 

 mountains, preference is given to the stems which are about to put 

 out branches and leaves. Early in the month of June the cane.' are 

 cut into pieces, from five to seven feet long, and placed in a pit, 

 which is supplied with water. After soaking for several weeks the 

 canes are beaten with a mallet, in order to remove the thick bark 

 and green skin. The remaining filaments, resembling a fine sort 

 of hemp, are treated with lime and water, raised to a certain tem- 

 jDerature. After remaining in this bath for about a week, the 

 filaments are removed, washed with cold water, passed through a 

 lye made of wood ashes, and then placed in a boiler. This process 

 is repeated until the material begins to grow putrid, when it is 

 transferred to a mortar and pounded into pulp by means of water 

 power, after which the mass is treated with bleaching powder. 

 The pulp thus prepared is made by hand into sheets of various 

 thickness, by means of a web of silk tissue within a light frame, 

 on to which the workman places the required quantity of pulp. 

 When the water has run off" from the corners of the frame, he 

 turns the sheet over on to a large table, when it is pressed. Each 

 sheet is afterward raised and dried separately in a kiln built for 

 that purpose. Writing paper is made from the finest part of the 

 bamboo material. Another kind is made by mixing rice straw 

 with the bamboo fiber. A very strong paper used for window 

 blinds and other articles, which in this country are generally con- 

 structed of woven substances, is made by mixing sixty per cent of 

 the bark obtained from a tree called " tchou " with forty per cent 

 of bamboo material. Another variety of strong paper is obtained 

 from the bark of the mulberry tree, and is used in the breeding 

 and culture of silkworms. The same material, made from a thinner 

 pulp, is employed in the manufacture of umbrellas, fans and fire- 

 screens. Bark paper, which is to be painted, is first passed through 

 a solution of alum water to destroy the fine filaments, which are 

 commonly found on the upper side of the sheet, as it lies in the 

 silk tissue frame — the lower side in contact with the tissue beius: 



