486 
BARBADOES AND SOCOTRINE ALOES. 
chief reason why Socotrine aloes was preferred to the 
Barbadoes. 
Mr. Simmonds said that the superiority of the Barbadoes 
aloes was probably owing to the pains taken in the culti¬ 
vation. The plant was grown, and the extract was prepared, 
by negroes, who were small holders of land, and who bestowed 
great care both on the plant and the preparation of the 
extract. Cape aloes was the produce of a wild plant. 
Professor Bently thought the real reason why Socotrine was 
preferred was the agreeable aroma it possessed, from which it 
was inferred that it must have a more agreeable action. 
From Dr. Pereira’s experiments, and those of Dr. Clutter- 
buck, it would appear that there was really no difference in 
the action of the various kinds of aloes on man; but it must 
have been from observing the better effects of it, that the 
Barbadoes was universally preferred for animals. With regard 
to aloine, he had observed that the crystals of that body 
obtained from the different kinds certainly differed in size, 
and somewhat also in form. 
Mr. Deane said that when aloine was heated up to a certain 
temperature the crystals were destroyed. He did not believe 
that the purgative property of the drug depended on the 
aloine, for Socotrine aloes, from which aloine could not be 
made, purged as well as the others. He added, that he had 
found the preparation of Dr. Marshall Hall’s pill, the pilula 
aloes cum sapone of the present Pharmacopoeia, was much 
improved by the addition of a few drops of liquor potassae 
when making the mass. In this way a perfectly homoge¬ 
neous mass that always rolled well was obtained, which was 
not the case when the Pharmacopoeia form was strictly 
adhered to The reason of this, he thought, was, that the 
acid in the treacle effected some decomposition of the soap, 
which was prevented by the use of the liquor potassoe. 
The Chairman [Mr. Morson) remarked that the whole subject 
of aloes was one of great importance, and deserved an 
extended study. Barbadoes aloes was preferred, because the 
aloine was most readily obtained from it, and aloine was 
supposed to be the active principle of the drug. This, how¬ 
ever, was disputed by M. Kobiquet and other Continental 
writers, some of whom asserted that it was not a purgative. 
He repeated that the question was a most important one, the 
chemistry of which was worthy to be made the subject of a 
prize essay. The aloine found in commerce was a light 
yellow crystalline powder, which was used as a purgative; 
but how r it was prepared on the large scale he did not know. 
The liquid juice of aloes imported deposited it in large 
quantities. 
