374 



Dr. C. R.A. Wright on the 



[Mar, 9, 



The yield of this base from the codeia used being but small (about 4 

 per cent.), no attempt was made to isolate the base itself ; carbonate of 

 soda throws down from the hydrobromate solution a white precipitate 

 which is soluble in alcohol, ether, benzol, and chloroform ; by exposure 

 to air it rapidly becomes coloured, and finally acquires a very dark green 

 tint. Its qualitative reactions are identical with those of apomorphia ; the 

 colour-reactions of the two with Fe 2 Cl 6 , N0 3 H, and S0 4 H 2 +K 2 Cr 2 7 

 being indistinguishable when examined side by side. Its physiological 

 effects, however, are different ; three-tenths of a grain of the hydrobromate 

 administered by the mouth to a dog producing no appreciable effect, whilst 

 a much less dose of apomorphia produces speedy vomiting. 



The third base is conveniently obtained, as hydrobromate, by treating 

 codeia with three times its weight of 48 per cent. H Br for two hours on 

 the water-bath, precipitating the product (diluted with water) by excess 

 of carbonate of soda, collecting on filters, and well draining from the 

 mother-liquors, and finally extracting with ether until scarcely anything 

 more is taken up ; care must be taken to have as little watery fluid as pos- 

 sible present, otherwise the insoluble substance forms a sort of lather, on 

 agitation from which the ether will not separate. The insoluble substance 

 is then dissolved in the least possible quantity of weak hydrobromic acid 

 and fractionally precipitated by cautious addition of stronger acid ; the se- 

 cond precipitate is dissolved up in water, in which it is readily soluble, and 

 a few drops of carbonate-of-soda solution added. The filtrate from this 

 yields, with strong H Br, nearly white flakes, which are wholly void of crys- 

 talline character under the microscope. These remain solid at 100° if 

 previously completely dried over S0 4 H 2 ; but if warmed while moist, be- 

 come a more or less coloured tar. Dried at 100°, the following numbers 

 were obtained : — 



0-3440 grm. gave 0'6810 C0 2 and 0-1740 H 2 0. 

 0-3425 grm. gave 0-6685 CO and 0-1680 H 2 0. 

 0*5615 grm. burnt with soda-lime gave 0*1310 Pt. 

 0-3200 grm. boiled with N0 3 H and AgN0 3 gave 0*1330 AgBr. 

 and 0-0315 Ag. 



Calculated. Found. 



C 72 864 54-03 53'99 53'23 



H* 7 87 5-44 5-61 5-45 



N 4 ".. 56 3-50 3-33 



0* 2 192 12-01 



Br' 400 25-02 24'97 



C 72 H 83 BrN 4 12 ,4HBr 1599 100 00 



Carbonate of soda throws down from the hydrobromate a nearly white 



