Seaweed and its Uses. 335 



about 80,000 cwt. being shipped annually from these two 

 ports. At Shanghai the imports reach about 170,000 cwt. 

 The trade in Japanese seaweed has year after year been 

 assuming more ample dimensions in China. It is princi- 

 pally made use of by the poorer classes. 



A very interesting product, called kanten or vegetable 

 isinglass, a species of gelose derived either from Gelidium 

 corneum, or Plocaria lichenoides, is made in China and 

 Japan, and has been imported into this country, in the 

 shape of flat and moulded square tablets and in bundles of 

 strips, under the name of seaweed isinglass. It is known in 

 Cochin China as hai thao, and has been used in France 

 in several industries, especially in preparing gold-beater's 

 skin, and for rendering tissues impermeable. It is only 

 soluble in boiling water, and it takes up about 500 times 

 its own weight of the fluid. 



The mode of manufacture is as follows ; The seaweed 

 called tengnsa is carefully washed and afterwards boiled, 

 so as to form a gluish decoction, which is strained off 

 and put into square boxes. When cooled, it forms a stiff 

 jelly, which can easily be divided into squares of a foot in 

 length. 



The manner in which the surplus water is removed is 

 most ingenious, and worthy of notice. The jelly prisms 

 are exposed in the open air during a cold night, and 

 allowed to freeze. During the day the sun melts the water, 

 which runs off, leaving behind what one might term the 

 skeleton of a white horny substance, which is extremely 

 light, and easily diluted in hot water ; when cooled, it again 

 forms a stiff jelly. This article, which is already to a 

 certain extent known in Europe, can be applied to many 

 uses, viz., for cooking purposes, for making bonbons and 

 jellies, for clarifying liquids, as a substitute for animal 



