On a very singular Sulphuretted Nitrogenous Compound, 24<7 



only know that it contains the joint weights of potassium and 

 chlorine), the logarithmic equations make no suggestion upon 

 this subject. All the above experiments might have been accu- 

 rately performed and symbolically expressed by a person totally 

 ignorant of the " constitution " of ferric salts or of potassic sul- 

 phocyanide ; and the reagent might have been extremely impure, 

 provided that it produced a red coloration. What we owe to 

 Esson and Gladstone we might have inherited from Wenzel or 

 Cavendish. 



12 Pemberton Terrace,, 

 St. John's Park. N. 



XXXV. On a very singular Sulphuretted Nitrogenous Compound, 

 obtained by the Action of Sulphide of Ammonium on the Hydrate 

 of Chloral. By Edmund W. Davy, A.M., M.D., M.R.LA., 

 Professor of Forensic Medicine, Royal College of Surgeons, 

 Ireland, and late Professor of Agricultural Chemistry, Royal 

 Dublin Society*. 



THE substance termed hydrate of chloral, or chloral hydrate, 

 from the many valuable therapeutic properties it has re- 

 cently been found to possess, has within the last four or five 

 years been prepared in considerable quantities, and has become 

 an article of some commercial importance ; and numerous as 

 are the useful applications which have already been made of 

 that substance in medicine, there can be but little doubt that 

 their number may be greatly increased; so that we may justly 

 regard chloral hydrate as one of the most, if not the most, im- 

 portant of the recent additions to our materia medica. 



It being thus a substance of such practical importance, any 

 information which may tend to extend our knowledge of its che- 

 mical properties and relations should not, I conceive, be regarded 

 as devoid of interest. I shall therefore briefly state the results 

 of some observations which I have recently made as to the action 

 of sulphide of ammonium on that substance (a subject that has 

 been but little studied), and describe the properties of a very 

 singular compound thereby produced, the constitution of which, 

 as far as I am aware, has not hitherto been determined. 



When sulphide of ammonium is added to an aqueous solution 

 of chloral hydrate, the mixture after a few moments acquires a 

 deep yellow colour, and, rapidly becoming orange, passes to 

 a reddish brown, which finally assumes so dark an appearance 

 that the liquid, when in any quantity, looks almost black by 

 reflected light. It was also observed, after the mixture had 



* Communicated by the Author. 



