City and Guilds Institute Examinations in Gas Subjects The Papers. Name. ... Elaboration should be avoided, a simple line drawing clearly indicating the principles involved being sufficient. Diploma. in. Gas. Engineering. In the examination for the diploma in gas engineering, considerable improvement was shown and several excellent papers were submitted. ... Copies of the 1931 examination questions set by the Institution can be obtained on application to the secretary, Mr. J. R. W.anbsp;...