1815.] Elements of Organic Nature are combined. 26') 



Sugar of milk 12-8 100 



Oxide of lead 87*2 681 



100-0 



But 174-15 X 4 = 69G-6; hence it follows, that in the sub- 

 saccolate the sugar of milk is combined with four times as much 

 base as in the neutral saccolate. ... r -j 



As it is easier to obtain this last combination with excess ol oxide 

 in a state of purity than the others, I consider the result of its 

 analysis as nearer the truth than that of the others. It is clear that 

 the <ugar of milk and oxide of lead in it ought to contain equal 

 quanthies of oxvgen. 681 of oxide of lead contain 48-65; and we 

 shall see immediately, from other data, that the sugar of milk 

 ought to contain exactly the same quantity. . , , • r 



I exposed five parts of pulverized sugar of milk to the action of 

 ammoniacal gas ; tl^eir action on each other was very slow, espe- 

 cially at the commencement. The absorption continued tor 15 

 days. The sugar of milk had then diminished a little in bulk, and 

 liad assumed a yellowish colour, owing to some slight alteration in 

 its composition. It now weighed 5-G2, and exhaled a strong smell 

 of ammonia. I left it under a glass jar, not shut, and weighed it 

 at the end of every half hour. It diminished in weight with a 

 great deal of rapiditv, so that after two hours it weighed only 5-33. 

 After this I found tli'at it scarcely lost any more weight; for m 18 

 liours the loss did not exceed 0-05. From this we see tiiat sugar 

 of milk forms at least two saccolates of ammonia, m whicn the 

 proportions of ammonia are as 1 : 2. Now we have seen that 100 

 parts of crystallized suirar of milk contain V2-} per cent, of com- 

 bined water, and that the same quantity of sugar of milk absorbs 

 12-4 of ammonia. Tlie oxygen of this last is 6*7, and that of the 

 first 10-9, or very nearly twice as much ; so that we have here 

 found the' same ratio between the ammonia and the water of com- 

 bination as ill common sugar. And tliough the sugar of m:lk ab- 

 sorbed a little more ammonia than it ought to have done according 

 to calculation, this seems to have been owing to a commencement 

 of decomposition in it. In fact, when saccolate erf ammonia was 

 dissolved in water, and muriatic acid mixed with the solution, there 

 wris a disengagement of some carbonic acid, which sufficiently ex- 

 plains the excess of ammonia al)soibe(l. I ought, besides, to make 

 the general observation, that the tendency of sugar of milk to be 

 decomposed by the bases, which appears to exceed that of tannin 

 and gallic acid, prevents any of my exi)eriments on its capacity of 

 saturation from beintr decisive; but as they correspond sufficiently 

 with tl.r jirobable c(m!positi«ni of sugar of milk, I consider them as 

 probal)lv very near the truth. . , ,. r> . u i 



Supposing crystallized sugar of milk to be O + t + 2 H, and 

 that it contains a quantity of water the oxygen in which is ^ of 

 the whole found in the substance, there ought to remain tor pure 

 I 



