Chap. V. MR. WARRINGTON'S OBSERVATIONS. 95 



the other I have seen only in the north of China.* 

 It is less heavy than common Prussian blue, of a 

 bright pale tint, and very beautiful. Turmeric root 

 is frequently employed in Canton, but I did not 

 observe it in use in Hwuy-chow. 



I procured samples of these ingredients from the 

 Chinamen in the factory, in order that there might 

 be no mistake as to what they really were. These 

 were sent home to the Great Exhibition last year, 

 and a portion of them submitted to Mr. Warrington, 

 of Apothecaries' Hall, whose investigations in con- 

 nexion with this subject are well known. In a paper 

 read by him before the Chemical Society, and pub- 

 lished in its ' Memoirs and Proceedings,' he says, — 



" Mr. Fortune has forwarded from the north of 

 China, for the Industrial Exhibition, specimens of 

 these materials (tea dyes), which, from their appear- 

 ance, there can be no hesitation in stating are fibrous 

 gypsum (calcined), turmeric root, and Prussian blue ; 

 the latter of a bright pale tint, most likely from 

 admixture with alumina or porcelain-clay, which 

 admixture may account for the alumina and silica 

 found as stated in my previous paper, and the pre- 

 sence of which was then attributed possibly to the 

 employment of kaolin or agalmatolite." 



* I formerly mistook this for a kind of indigo. 



