270 ON THE SEEDS OF THE RICINUS COMMUNIS. 
mas communicated some farther details concerning this 
highly interesting substance. 
The tube containing the crystallized nitric acid exhibited 
to the members of the Academy having been left to itself 
became liquid. On attempting to make the substance 
crystallize again by means of a refrigerating mixture, the 
tube was destroyed with a violent detonation, owing to 
some accidental vibration. I suspect that the dry nitric 
aeid was gradually decomposed into hyponitric acid and 
oxygen, and that the latter, from its state of compression, 
gave rise to the explosion. It is necessary therefore to 
handle this new product with precaution. Owing to this 
accident I am unfortunately unable to present to the 
Academy a very beautiful specimen of anhydrous nitric 
acid which M. Deville forwarded to me, the crystals of 
which were of considerable size, and from their beauty 
most readily admitted of the fundamental form of this sub- 
stance being determined with certainty. — Chem. Gazette. 
ART. LXL— ON THE SEEDS OF THE RICINUS COMMUNIS. 
By M. Callond. 
M. Callond has been engaged for several years in the 
examination of the seeds of the Ricinus communis, or castor- 
oil plant. It is well known that these seeds yield a mild 
purgative oil (castor-oil ;) but the mark from which the oil 
has been pressed retains an emetico-cathartic principle 
which the author considers to possess much interest. The 
castor-seeds, administered in doses of one or two drachms, 
either in their natural state, or made into an emulsion, 
generally produce hypercatharsis accompanied by vomiting. 
The mark or residue from which the oil has been pressed 
operates with nearly the same energy as the seeds in their 
natural state, from which it has been inferred that the mild 
