ON SOME VEGETABLE ALKALOIDS. 35 



iodide, chloride, &c. ; and in the following pages I make use of these terms, 

 without, however, making any alteration in the conventional nomenclature for 

 the base. 



The salts of ethylostrychnine, generally, are characterized by their beautifully 

 crystalline nature, and the facility with which they may be obtained pure. I have 

 analysed a few, as affording a favourable opportunity of examining the combina- 

 tions of one of these derivatives from a natural fixed alkaloid. 



Nitrate of Ethylostrychnine. — This compound is readily formed by double de- 

 composition from the preceding, by use of nitrate of silver in warm dilute solutions. 

 It is easily soluble in boiling water, but of extremely sparing solubility in this 

 menstruum when cold ; so much so, that I have used this property as a test of the 

 existence of the base on many occasions ; a solution containing it, even when 

 tolerably dilute, depositing, on the addition of a little nitric acid, in a short time, 

 very fine four-sided prismatic crystals ; in more concentrated fluids their appear- 

 ance is immediate. The salt, in a pure state, is in colourless prisms of high re- 

 fractive power, which may be obtained of great beauty from dilute aqueous fluids. 

 Its analysis gave the following results : — 





f 4-555 grains, 

 { 10-790 ... 

 [ 2-680 ... 



Pound. 



. . 64-60 

 . . 6-53 



, dried at 212°, gave 

 carbonic acid, and 

 water. 



Calculation. 





Carbon, 



Hydrogen, 

 Nitrogen, . 

 Oxygen, . 



64-94 C i6 

 6-35 H 27 

 9-88 N 3 



18-83 O 10 



276 

 27 

 42 

 80 



100-00 100-00 425 



which agree precisely with the formula — 



C 46 H 26 N 2 4 , HO, N0 5 = C 46 H 27 N 2 4 NO fi . 



Its crystals contain no water. 



Chromates of Ethylostrychnine. — Both neutral and acid chromate of potass 

 yield precipitates w ith salts of the base ; the former giving, even in dilute fluids, 

 short prismatic yellow crystals, and the latter tufts of silky needles. As the 

 number of bichromates, of whose analysis we are in possession, is in reality very 

 small, being limited, I believe, to those of potass and ammonia, whose constitu- 

 tion is peculiar, I examined the salt in the present instance, to see if it were quite 

 analogous to these compounds, which it does not appear to be. 



Bichromate of ethylostrychnine is deposited from strong mixed solutions of the 

 appropriate salts in very beautiful transparent plates of a golden yellow colour ; 

 it falls, as just mentioned, from more dilute fluids, in tufts of needles ; it is readily 



VOL. XXI. PART. I. K 



