102 ACETIC ALDEHYDE. 



at 152, and at a somewhat higher temperature is con- 

 verted into gas. The specific gravity of the vapor is 

 1.06, corresponding to the simpler formula CH 2 0. 



Formylsulphaldehyde, C 3 H 6 S 3 . When the liquid 

 obtained by oxidizing methyl alcohol, or when pure 

 oxymethylene, is saturated with sulphuretted hydro- 

 gen, a substance, having an alliaceous odor, separates, 

 which dissolves, when the liquid is heated with half 

 its volume of concentrated hydrochloric acid, and 

 crystallizes out on cooling. Is also produced by the 

 action of hydrogen in statu nascendi (zinc and hydro- 

 chloric acid) on carbon bisulphide, sulphocyanic acid, 

 ethyl and allyl mustard-oils ; and by treating methy- 

 lene iodide with an alcoholic solution of sodium sul- 

 phide. Fine, needly crystals, which fuse at 218, and 

 are volatile without decomposition. Difficultly soluble 

 in boiling water, more readily in alcohol and ether. 



Combines with silver nitrate, mercury chloride, and 

 platinum chloride, forming crystalline compounds. 



Hexamethyleneamine, (CH 2 ) 6 N 4 . Is formed when 

 ammonia is conducted over oxymethylene, at first at 

 the ordinary temperature and finally with the aid of 

 gentle heat. Clear, colorless, lustrous, rhombohedric 

 crystals. Sublimable when very carefully heated. 

 Easily soluble in water and boiling alcohol, but slightly 

 soluble in cold alcohol and in ether. Has an alkaline 

 reaction, and yields salts with acids. 



The hydrochlorate, C 6 H 12 N 4 .HC1, crystallizes in long, 

 colorless needles, which are easily soluble in water. 



2. Acetic Aldehyde. 

 C 2 H 4 = CEP.CHO. 



Preparation. By imperfect oxidation of alcohol. 

 2 parts of alcohol are distilled with 3 parts manga- 

 nese peroxide, 3 parts sulphuric acid, and 2 parts water 

 until that which passes over begins to have an acid 

 reaction. The distillate is rectified over calcium chlo- 

 ride, then mixed with an equal volume of ether, and 



