162 
April 23rd, 1838. 
SIR Wo. R. HAMILTON, A.M., President, in the Chair. 
The President continued the reading of the paper by the 
Rev. Dr. Hincks, on the Years and Cycles of the ancient 
Egyptians. 
Dr. Apjohn communicated a paper upon the subject of 
a new and very complicated compound, consisting of iodine, 
iodide of potassium, and the essential oil of cinnamon. 
This compound he stated to have been first observed in 
the winter of 1837, in a solution prescribed by a medical 
gentleman of this city, of iodine and iodide of potassium in 
cinnamon water. It is best obtained by adding toa gallon of 
cinnamon water four ounces of iodide of potassium, and forty 
grains of iodine, dissolved in a minimum of cold water. Upon 
admixture, the solution becomes turbid, and if the tempera- 
rature be at or close to 32°, the deposit becomes crystalline, 
and slowly subsides. The properties of these crystals were 
detailed, and a succinct account given of the different steps 
of the process employed for effecting their analysis. 
As the result of a number of experiments, the author ar- 
rived at the following numbers, expressing the composition: 
of 100 parts of the compound. 
Iodide of potassium . 12.55 
Iodine . . . . , 98:14 
Oilofcinnamon . . 59.3] 
100. 
The empirical formula deducible from these results is 
IK + I3 + C7, 
in which ci represents Cis Hg 02, the atom of oil of cinnamon, 
