This improvement, simple as it is in appearance, presents several other advantages which immediately treble the output.
The special object of M.Claude was to obtain oxygen in a practical manner by the actual distillation of liquid air.

Since nitrogen boils at -194 deg.

and oxygen at -180.5 deg.

C., if liquid air be evaporated, the nitrogen escapes, especially at the commencement of the evaporation, while the oxygen concentrates in the residual liquid, which finally consists of pure oxygen, while at the same time the temperature rises to the boiling-point (-180.5 deg.

C.) of oxygen.