ACIDUM HYDROCYANICUM DILUTUM. 165 



yETHYL IODIDUM. IODIDE OF ETHYL. HYDRIO- 

 DIG ETHER. C 2 H 5 I. (Not Officinal.') 



Source. Made by adding iodine to a mixture of Alcohol 

 and Phosphorus, distilling, and purifying. 5C 2 H 5 HO -f Pl- 

 (iodide of phosphorus) = 5C 2 H 5 I + H 3 P0 4 + H 2 0. 



Characters. A colourless volatile liquid, with a peculiar 

 powerful odour, and a pungent taste. Sp. gr., 1-92. Non- 

 inflammable. Decomposed by light, yielding iodine. Soluble 

 in alcohol and ether ; very sparingly soluble in water. 



Dose. 5 to 20 min. Inhaled from a broken capsule. 



ACTION AND USES. 



Iodide of ethyl acts chiefly by virtue of the iodine ele- 

 ment, and very slightly, if at all, as an anaesthetic ethyl com- 

 pound. It introduces iodine very rapidly into the system, and 

 has been chiefly used to stimulate the respiratory passages, and 

 thus to act as an antispasmodic in asthma attended by scanty 

 or tough secretion. In some instances it gives instant relief. 



AGIDUM HYDROOYAMGUM DILUTUM. 



DILUTED HYDROCYANIC ACID. 

 " Prussic Acid." Hydrocyanic acid, HCN, dis- 

 solved in water, and constituting 2 per cent., by weight 

 of the solution. 



Source. Made by distilling solutions of Ferrocyanide of 

 Potassium and Sulphuric Acid. 2K 4 Fe(CN) 6 + 6H 3 S0 4 = 

 6HCN + Fe 2 K 2 (CN) 6 + 6KHSO 4 . 



Characters. A colourless liquid, with a peculiar penetrating 

 odour. Sp. gr., 0-997. Faintly acid. 



Incompatibles. Salts of silver, copper, iron, red oxide of 

 mercury, and sulphides. 



Impurities. Sulphuric and hydrochloric acids. 



Dose. 2 to 8 min, 



Preparation. 



YlPOr Add* Hydrocyanicji. 10 min. in 1 fl.dr. cold 

 water. 



Hydrocyanic acid is also contained in Aqua Lauro- 

 cerasi. See also Amygdala Amara, page 239. 



