ON ALOINE. 287 
The formula derivable from these analyses is C 34 , H 19 , O l5 , 
which, as we shall presently see, is =: C 34 H 13 0 14 -f HO, or 
aloine with one equivalent of water. 
The aloine which had been dried in vacvo was next heated 
in the water-bath for five or six hours, and was also subjected 
to analysis. 
I. 0.251 grm. aloine dried at 212° F. gave 0.550 carbonic 
acid and 0.128 water. 
II. 0.2535 grm. aloine dried at 212° F. gave 0.564 carbonic 
acid and 0.129 water. 
III. 0.234 grm. aloine dried at 212° F. gave 0.521 carbonic 
acid and 0.114 water. 
Calculated numbers. I. II. III. 
34 C. 2550 61.07 60.51 60.67 60.72 
18 H. 225 5.39 5.66 5.65 5.42 
14 0. 1400 33.54 33.83 33.68 33.86 
4175 100.00 100.00 100.00 100.00 
The aloine employed in these analyses was prepared at three 
different times. These results give C 34 H 1S 0 14 as the formula 
of anhydrous aloine, that dried in vacuo being a hydrate with 
one equivalent of water. 
When the aloine was allowed to remain in the water-bath for 
more than six hours, it continued slowly to lose weight, appa¬ 
rently owing to its undergoing partial decomposition by the for¬ 
mation of a brownish resin. The loss of weight gradually con¬ 
tinued for a week or more, but became very rapid when the 
aloine was heated to 302° F., when it melted, forming a dark 
brownish mass, which, when cooled, became as hard and brittle 
as colophonium : it still, however, contained a good deal of 
unaltered aloine, as I ascertained by crystallizing it out with hot 
spirits and analyzing it. Much of the aloine had been changed, 
most probably by oxidation, into a dark brown uncrystallizable 
resin. 
Brom-aloine ,—When an excess of bromine is poured into a 
cold aqueous solution of aloine, a bright yellow precipitate is 
immediately produced, the amount of which increases on stand¬ 
ing, while at the same time the supernatant liquid becomes very 
acid from containing free hydrobromic acid. The precipitate, 
after it has been washed with cold water to remove adhering 
acid, is dissolved in hot spirits of wine; and on the cooling of 
the solution it is deposited in bright yellow needles radiating 
from centres, which attach themselves to the bottom and sides 
of the containing vessel. 
The crystals of brom-aloine are considerably broader than 
those of aloine, and have a richer yellow colour and a higher 
lustre. Brom-aloine is quite neutral to test-paper, and is not 
