Gas chromatography was used for qualitative and quantitative determination of the products of the hydrolysis of uranium carbides and of thorium carbides. The products were separated on four columns: 5A molecular seive, di-2-ethylhexyl sebacate, tricresyl phosphate, and silica gel modified with squalane. The hydrocarbons were identified by use of known gaseous and liquid alkanes, alkenes, and alkynes. The numerical data were obtained by IBM 7090 computation.