. The methods described are suitable for preparing the pure compounds in quantities of 1 kg or more. For each of the hydrocarbons and also for n-heptane and 2.2,4-trimethylpentane we have determined accurate values for the boiling point, melting point, densities at 15" and 20" or at 20" and 25", refractive indices and molecular refractions at the same temperatures for the wave lengths 6563. 5876, 4861, 4341 A. W e have also recorded accurate values for the surface tension at 20" and for the parachor. The critical solution temperatures with aniline have also been determined.

No abstract

No abstract

No abstract

A method is described for filling thin‐walled ampullae with volatile liquids with the total exclusion of air and water. In this way it is possible to weigh out accurately the amount of material used for a heat of combustion measurement before the experiment is made. To aid the combustion reaction in proceeding to completion a high platinum crucible is used covered with a platinum shield. In a normal heat of combustion reaction it is impossible to detect the presence of carbon monoxide in the combustion gases. The reproducibility obtained is 0.01‐0.02%.