Chemical Science. 205 



When atropia and potassa are mixed and raised to a red 

 heat, the as^es (solution?) mingled with muriate of iron, pro- 

 duces a brilliant red colour. 



Hyoscyamia is extracted from the hyoscyamus niger, and is 

 not easily altered even at a red heat. It crystaUizes in long 

 prisms, and when saturate with sulphuric acid or nitric acid, 

 forms very characteristic salts. 



In examining the constituent alkaline principles of narcotic 

 plants, much care must be taken, as the venomous properties 

 of the plants are concentrated in them. The vapour is very in- 

 jurious to the eyes, and the smallest fragment placed on the 

 tongue is extremely dangerous — Jour, de Phys. XCI. p. 239. 



1 0. Lupulin, or the active Principle of the Hop. — Dr. A.W. Ives, 

 of New York, has lately made experiments on the hop, which 

 prove that its characteristic properties reside in a substance 

 forming not more than one-sixth part of the weight of the hop, 

 and easily separable from it. It was observed, that on re- 

 moving some hops from a bag in which they had been pre- 

 served for three years, an impalpable yellow powder was left 

 behind which, when sifted, appeared quite pure ; this has 

 been called lupulin, it is peculiar to the female plant, and is 

 probably secreted by the nectaria. 



From various experiments made on it, Dr. Ives inferred that 

 lupulin contains a very subtle aroma which is yielded to water 

 and to alcohol, and which is rapidly dissipated at a high heat; 

 that no essential oil can be detected by distillation in any 

 portion of the hop ; that the lupulin contains an extractive 

 matter which is soluble only in water ; that it contains tannin, 

 gallic acid, and a bitter principle which are soluble in alcohol 

 and water ; that it contains resin which is soluble in alcohol 

 and ether, and wax which is soluble only in alkalies and boiling 

 ether ; that it contains neither mucilage, gum, nor gum resin ; 

 that the aromatic and bitter properties of the lupulin are more 

 readily and completely imbibed by alcohol than by water, and 

 much sooner by both when hot than when cold ; that about 

 five-eighths of the whole substance is soluble in water, alcohol, 

 and ether, there being about three-eighths of it vegetable 

 fibrous matter ; 120 grains of lupulin contain about 



Tannin 5 gr. 



Extractive matter. ... 10 



Bitter principle 11 



Wax 12 



Resin 36 



Lignin 46 



Hops from which all the lupulin had been separated when 

 acted upon by water, alcohol, S^c. gave a portion of extract 



