64 Professor Boscoe [Feb. 21, 



The ammonia- water of the vinasse resembles that of the coal-gas 

 manufacture in so far as it contains carbonate, sulphydrate, and 

 hydrocyanide of ammonia ; but it differs from this (and approximates 

 to the products of the dry distillation of wood) by containing in 

 addition methyl alcohol, methyl sulphide, methyl cyanide, many of 

 the members of the fatty acid series, and, most remarkable of all, 

 large quantities of the salts of trimetliylamine. 



The tar, on re-distillation, yields more ammonia-water, a large 

 number of oils, the alkaloids of the pyridene series, solid hydro- 

 carbons, carbolic acid, and lastly, a pitch of fine quality. 



The crude alkaline aqueous distillate is first neutralized by 

 sulphuric acid, and the saline solution evaporated, when crystals of 

 sulphate of ammonia are deposited ; and these, after separating and 

 draining off, leave a mother liquor, which contains the more soluble 

 sulphate of trimethylamine. During the process of concentration, 

 vapours of methyl alcohol, methyl cyanide, and other nitrils are given 

 off, these being condensed, and the cyanide used for the preparation 

 of ammonia and acetic acid by decomposing it with an alkali. 



Trimethylamine itself is at present of no commercial value, though 

 perhaps the time is not far distant when an important use for this 

 substance will be found. The question arises as to how this material 

 can be made to yield substances capable of ready employment in the 

 arts. This problem has been solved by M. Vincent in a most inge- 

 nious way. He finds that the hydrochlorate of trimethylamine, when 

 heated to a temperature of 260°, decomposes into (1) ammonia, (2) 

 free trimethylamine, and (3) chloride of methyl. 



3 NMegHCl = 2 NMeg + NH3 + 3 MeCl. 



By bubbling the vapours through hydrochloric acid the alkaline 

 gases are retained, and the gaseous chloride of methyl passes on to be 

 purified by washing with dilute caustic soda and drying with strong 

 sulphuric acid. This is then collected in a gas-holder, whence it is 

 pumped into strong receivers and condensed. 



The construction of these receivers is shown in Fig. 1. They 

 consist of strong wrought-iron cylinders, tested to resist a pressure of 

 20 kilos, per square centimetre, and containing 50, 110, 220 kilos, 

 chloride of methyl. The liquid is drawn from these receivers by 

 opening the screw tap D, which is covered by a cap C, to prevent 

 injury during transit. 



Both ammonia and chloride of methyl are, however, substances 

 possessing a considerable commercial value. The latter compound 

 has up to this time, indeed, not been obtained in large quantities, but 

 it can be employed for two distinct purposes : (1) it serves as a means 

 of producing artificial cold; (2) it is most valuable for preparing 

 methylated dyes, which are at present costly, inasmuch as they havo 

 hitherto been obtained by the use of methyl iodide, an expensive 

 substance. 



Methyl chloride was discovered in 1804 by MM. Dumas and 



