836 
PROFESSOR GRAHAM ON THE DIFFUSION OF LIQUIDS. 
41. Hydrochlorate of Strychnine. 
Time of diffusion 1T43 days. The crystallized salt was assumed to be of the com- 
position C 42 H 22 N 2 O 4 .IT Cl-f-SHO, with the equivalent 397*5. Hydrochlorate of 
strychnine, 2 per cent., density T0065, diffused at 64°*1, in six cells, 1 1*54, 1 1*62, 1 1*31 ; 
mean lT49grs. for two cells. The quantities refer to anhydrous salt, and were 
estimated from the chlorine, as with hydrochlorate of morphine. 
These two analogous salts appear to approach very closely in diffusibility. 
Diffusion from 2 per cent, solutions at 64°T ; two cells. 
Hydrochlorate of morphine .... 1T60 100 
Hydrochlorate of strychnine .... 1T49 99*05 
For a similar period of 1 T43 days, but at a lower temperature, 53°*4, the 1 per cent, 
solution of hydrochlorate of morphine gave a mean result of 5*49 grs. from two cells, 
and the hydrochlorate of strychnine 5*77 gi’S- from two cells. But the weights of chlo- 
ride of silver from which these numbers are deduced were too small to admit of much 
precision. 
The diffusion of these salts of organic bases in 11*43 days, is exceeded by the diffu- 
sion of chloride of ammonium or potassium in 5*71 days, or half the former time. The 
vegeto-alkalies appear thus to be divided from ammonia and potash. 
'J'he new observations of the present paper are favourable to the existence of a 
relation amounting to close similarity or equality in diffusibility between certain 
classes of substances. 
The chlorides and nitrates of the same metal generally exhibit this corespondence, 
as in the chloride of calcium and nitrate of lime, the chloride of sodium and nitrate 
of soda, and also in hydrochloric and nitric acids. 
Isomorphous salts exhibit the same relation, as has been observed in the chlorides, 
bromides and iodides of potassium, sodium and hydrogen, in various salts of baryta, 
strontia and lead, in numerous magnesian salts, in the salts of silver, soda, and pro- 
bably those of suboxide of copper, and in several additional salts of potash and 
ammonia. 
Corresponding salts of two of the vegeto-alkalies are also found to be equidiffusive. 
Before discussing the relations between the different groups of equidiffusive sub- 
stances which are thus formed, it will be necessary to examine their diffusion at 
widely different temperatures, a subject attended with considerable difficulty. 
INDEX 
