532 LAURACEiE. 



If thin sections of cassia bark are moistened with a dilute solution 

 of perchloride of iron, the contents of the parenchymatous part of the 

 whole tissue assume a dingy brown colour ; in the outer layers the starch 

 granules even are coloured. Tannic matter is consequently one of the 

 chief constituents of the bark ; the very cell- walls are also imbued with 

 it. A decoction of the bark is turned blackish green by a persalt of 

 iron. 



If cassia bark (or Ceylon cinnamon) is exhausted by cold ivater, the 

 clear liquid becomes turbid on addition of iodine ; the same occurs if a 

 concentrated solution of iodide of potassium is added. An abundant 

 precipitate is produced by addition of iodine dissolved in the potassium 

 salt. The colour of iodine then disappears. There is consequently a 

 substance present which unites with iodine ; and in fact, if to a 

 decoction of cassia or cinnamon the said solution of iodine is added, it 

 strikes a bright blue coloration, due to stai-ch. But the colour quickly 

 disappears, and becomes permanent only after much of the test has 

 been added. We have not ascei'tained the nature of the substance that 

 thus modifies the action of iodine : it can hardly be tannic matter, as 

 we have found the reaction to be the same when we used bark that 

 had been previously repeatedly treated with spirit of wine and then 

 several times with boiling ether. 



The mucilage contained in the gum-cells of the thinner quills of 

 cassia is easily dissolved by cold water, and may be precipitated together 

 with tannin by neutral acetate of lead, but not by alcohol. In the 

 thicker barks it appears less soluble, merely swelling into a slimy 



jelly. 



Commerce — Cassia lignea is exported from Canton in enormous 

 and increasing quantities. The shipments which in 1864 amounted to 



from the other ports of China cassia is not shipped to any extent. 

 England usually receives no more than about 1,000,000 lb. of cassia, of 

 which only 40,000 lb. appear to be consumed in the country. Hamburg 

 imports about 2,000,000 lb. annually immediately fi'om China. Yet in 

 1878 the quantity imported into London was 26,744 peculs (3,500,000 

 lb.), that received at Hamburg 13,548 peculs. 



Cassia lignea is exported in chests containing 2 peculs each. 



Oil of cassia was shipped from the south of China to the United 

 Kingdom, to the extent in 1869 of 47,5171b.; in 1870, of 28,389 lb." 

 Hamburg is also a very important place for this oil; in the official 

 statistics of that port for 1875 the imports from China are stated to 

 have amounted to 80,000 lb„ besides 10,000 lb. imported from Great 

 Britain; in 1876 Hamburg imported 5,900 lb. from China and 17,000 

 lb. from England. 



Uses — The same as those of cinnamon. 



1 Canton Trade Report for 1869. ^ Annual Statement of the Trade and 



^ Commfrcial Reports from H.M.Comuh Nav'ujation of the United Kint/dom for 



in China, presented to Parliament 1873,— 1870. 290.-66,650 were exported in 1877 



(Consul Robertson). from Pakhoi. 



