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stance, 6 grammes of oil of bitter almonds absorbed 1 1 grammes of 

 hydriodic acid gas. Analyses of the substance lead to the formula 

 C 42 H 18 O 2 I 4 , which will be observed to be 3 atoms of oil of bitter 

 almonds, in which 2(0 2 ) is replaced by 2(I 2 ). The authors pro- 

 pose for it the name Oxyiodide of Benzaldehyde. The substance 

 thus obtained melts at 28 C., and solidifies at about 25 C. into almost 

 colourless rhombic plates if rapidly cooled down. When in a liquid 

 state, the crystals mostly occur in groups of long needles. The 

 colour of the substance in a melted state is brownish yellow; at 

 moderate temperatures, and on standing in the air, it becomes still 

 darker in colour. It possesses a smell very much resembling cress. 

 It volatilizes at common temperatures, its vapour attacking the 

 eyes powerfully. Its vapour at higher temperatures, when carried 

 away by that of water, becomes more and more intolerable, pro- 

 ducing a very inflammatory effect on the eyes and nose, which is 

 more painful and permanent than that from acrolein. It is insoluble 

 and sinks in water, but can be distilled in the vapour of it. Watery 

 solutions of carbonates and sulphites of the alkalies do not act on it. 

 Alcoholic solution of potash decomposes it by degrees on heating a 

 little, producing much iodide of potassium, some benzoic acid, and 

 an oily body that remains dissolved in the alcohol, which is not oil 

 of bitter almonds. Alcoholic and watery solutions of ammonia 

 change it slowly into iodide of ammonium and oil of bitter almonds. 

 Boiled with solution of nitrate of silver, it yields iodide of silver, and 

 a smell of oil of bitter almonds. Concentrated hydrochloric acid 

 changes it by degrees, becoming brown ; concentrated sulphuric acid 

 dissolves it on heating, with the separation of iodine. 



In conclusion, the authors remark that the action of hydrochloric 

 acid on aldehyde may be regarded as consisting in the replacement 

 of two equivalents of oxygen by two of chlorine in one, two, or three 

 atoms of this body : thus, 



Aldehyde containing chlorine. 



1 atom of aldehyde C 4 H 4 O 2 C 4 H 4 C1 2 



2 C 8 H 8 O 4 C 8 H 8 O 2 C1 2 Lieben's body. 



3 CH0 



12126 



The action of hydriodic acid on oil of bitter almonds gives rise also 



