TRANSACTIONS OF THE SECTIONS. 49 
_ accidentally during the prevalence of cold weather, in a mixture pre- 
seribed by a physician, and which contained iodide of potassium, and 
iodine dissolved in cinnamon water, prepared by the ordinary pharma- 
ceutical process. It was first particularly noticed by Mr. Moore, of 
_ Anne Street, Dublin, in whose establishment the prescription was made 
up. He made several experiments upon it; and, having furnished Dr. 
Apjohn with a specimen of it, they undertook conjointly the further 
determination of its properties, and the investigation of its composition. 
It occurs in long capillary four-sided prisms, of a beautiful bronze 
aspect, melts at about 82°, dissolves in alcohol and ether, but is 
_ decomposed by water. This latter menstruum, however, has no action 
upon it when it holds iodide of potassium dissolved, or probably other , 
__ kinds of saline matter. Mercury effects its decomposition, an iodide of 
mercury being formed, and iodide of potassium, with (probably) cinna- 
mile, being liberated. By an elevated heat it is decomposed, iodide of 
potassium being left, with a considerable quantity of charcoal, while 
iodine, and an organic vapour smelling of the oil of cinnamon, pass 
off. Dr. Apjohn stated, that according to his experiments, which 
however were not completed, it would appear to be composed of one 
atom of iodide of potassium, associated with two of the subsesqui- 
iodide of cinnamile, as represented by the following formula : 
IK+2 (I Cin.) 
23 
This he stated to be the formula which most nearly expresses his _ 
analytic results: but he added, that he did not place much confidence 
in them ; and that, not having as yet been able to effect the combus- 
tion of the compound with oxide of copper, he should not be surprised 
at finding this formula materially corrected by the results of the 
_ further researches with which he stated himself and Mr. Moore to be 
at present occupied*. 
On a new Variety of Alum. By Dr. Arsjoun. 
The mineral in question was received from Mr. Atherton, an African 
gentleman, and was found on the eastern coast of the African con- 
- tinent, about midway between Graham’s Town and Algoa Bay. It 
occurs in fibrous masses, very similar to asbestos, having a beautiful 
satiny lustre, and splitting into threads which would appear to be 
quadrilateral prisms. In taste, solubility in water, and relation to 
several reagents, it closely resembles ordinary alum, but is distin- 
guished from it by containing protoxide of manganese, instead of an 
alkali, and by not assuming the octahedral form. In symbols it is 
represented by 
(3S0O+Al 0)+(S O+Mn O)+25 HO, 
a 3 23 8 
F _ * Dr. Apjohn has since found that this compound includes not Cinnamile but the 
oil of Cinnamon itself, and that its true formula is (IK+3 (I+Cin). (See Proceed- 
2 ~ 
F ings of the Royal Irish Academy for 1838, page 162.) 
VOL. vi. 1837. E 
