VOL. LXXVIII.] PHILOSOPHICAL TRANSACTIONS. 427 



of the decanted part of the liquor ; and the 4th and 5th show the quantity and 

 strength of the undecanted part of the liquor. The 6th column gives the strength 

 of both parts put together, or the strength of the whole mass; and the 7th is 

 the strength of the same acid, as it was determined before it was sent to Hudson's 

 Bay. Tlie strengths of the decanted and undecanted parts were found by satu- 

 rating the liquor returned home with marble; and that of the whole mass was in- 

 ferred by computation from the quantity and strength of the decanted and unde- 

 canted parts; and as the strength thus inferred never differs from that determined 

 before the liquors were sent to Hudson's Bay by more than -y-^ part of the whole, 

 it is not likely that the strengths of the decanted and undecanted parts here set 

 down should difftr from the truth by much more than that quantity. The 8th 

 column contains the freezing points found in the first method, or the temperature 

 of the liquors after the hasty congelation which took place on exposing them to 

 the cold without any frozen matter in them; and the Qth contains their tempera- 

 ture after the more gradual congelation which took place when they were cooled 

 with some frozen matter in them ; and as the unfrozen part of the acid was de- 

 canted immediately after the temperature had been observed, it follows, that this 

 column shows the true freezing points of the decanted liquors. In like manner 

 the 8th column shows the freezing points of that part of the liquor which re- 

 mained fluid in the first manner of trying the experiment ; but as the strength of 

 this part was not determined, the precise strengths to which these freezing points 

 correspond are unknown. Thus much however is certain, that these points must 

 be below those of the whole mass, and in all probability must be above those of 

 the decanted liquor ; as there is great reason to think that the quantity of frozen 

 matter was always less, and consequently the strength of the fluid part differed less 

 from that of the whole mass, in the first way of trying the experiment than in 

 the second. 



In all the foregoing acids the ice was heavier than the fluid part, and in con- 

 sequence subsided to the bottom ; a proof that it was the spirituou€ congelation 

 which had taken place in them: but in N° 13 the frozen part swam at top, which 

 shows that the congelation was of the aqueous kind. 



As the temperatures in the 9th column of the 

 foregoing table, are the freezing points answer- 

 ing to the strengths expressed in the 3d column; 

 and as — 41-i- is the freezing point answering to 

 the strength of .561 ; whence the freezing points 

 determined by these experiments, and their re- 

 spective strengths, are as annexed: 



By interpolation from these data, according to Newton's method *, it appears 

 * Princip. Math. Lib, 3, prop. 40, lem. 5, 

 3 I 2 



