This paper contains some further details of the properties and composition of the substance mentioned in a former note (Proceedings, vi. 75).

The substance is produced by the action of dry ammonia gas on dichloracetone. A low temperature favours its formation. It forms colourless needles, generally radiating from central points. It is extremely unstable, and can only be preserved in an atmosphere of dry ammonia. In vacuo over sulphuric acid, even at a temperature of 0° C., it decomposes into ammonia, dichloracetone, and a viscous substance, which has a smell recalling that of acetamide. The same decomposition takes place in dry air. Hydrochloric acid converts it into dichloracetone and chloride of ammonium. It may be fused in an atmosphere of dry ammonia, and sublimes readily at temperatures far below its fusing point.