Application of Cecil Boling and Alexander J. Tigges

MARTIN, Judge.

This is an appeal from a decision of the Board of Appeals of the United States Patent Office affirming the examiner’s rejection of claims 4 and 6, the only claims of appellants’ application for a patent on a heat exchange apparatus.

The appealed claims are as follows:

“4. In a heat exchange unit of the character described for cooling water wherein it is desirable to provide a high heat transfer relationship with the water and wherein the water may freeze and produce very substantial pressures upon the walls confining it during some conditions of operation, the combination of, a…