362 On the Distribution of 



action of chemical tests, there could be no doubt that they 

 consisted of indigo of a very inferior quality, and leaving a very 

 large proportion of inorganic matter by calcination, and of 

 porcelain clay. It is also curious that the very case selected 

 by Mr Seeman to illustrate the processes, is the conversion 

 by means of this facing or glaze, of a low quality of black 

 tea (Bohea Saushung) valued at about 4d. to 6d. the pound, 

 into high quality green teas valued at from Is. to Is. 6d. the 

 pound ; but although Mr Seeman does not allow this to be 

 an adulteration, yet surely he cannot deny that it is a fraud. 

 Another very good method which I have lately employed 

 of removing the colouring matter from the surface of green 

 teas for the purpose of microscopical investigation, and one 

 attended with very little trouble, is to take a piece of cream 

 coloured wove paper, or paper free from blue colouring ma- 

 terial, and having breathed on its surface or rendered it 

 slightly damp, to pour the sample of tea under examination 

 from the containing paper or vessel upon it* On then re- 

 moving it back again a quantity of the facing powder will be 

 found adhering to the surface of the paper ; and on placing 

 it under the microscope it will be found studded with the 

 colouring materials used, and the blue particles can be sub- 

 jected to the action of chemical tests with the greatest ease, 

 by placing a minute drop of the reagent on the granules with 

 the end of a small stirring rod or slip of glass, and noting the 

 effect. — (The Quarterly Journal of the Chemical Society, 

 Vol. v., No. 18, July 1852, p. 139.) 



On the Distribution of Granite Blocks from Ben Cruachan. 

 By William Hopkins, Esq., F.R.S., President of the 

 Geological Society. 



Mr W. Hopkins exhibited at the Meeting of the Bri- 

 tish Association at Ipswich, in 1851, a map of the lochs 

 and mountains around Ben Cruachan, with the distribu- 

 tion of the trains of granite blocks, to which he had 

 alluded last year at the Edinburgh meeting. He had for- 



