ON GASEOUS EXPLOSIONS. 159 



Note 37, by Mr. E. Griffiths and Dr. J. A. Harker, on ' A Method 



for the Determination of the Specific Heat of Gases at High 



Temperatures.' 

 Note 38, l)y Dr. Watson, on ' The Variation of the Mean Temperatui-e 



of the Cyhnder Contents with the Change of Fuel-Air Eatio for 



an Engine using Petrol, Benzol, and Alcohol.' 



Note 36. — At the first meeting of the Committee this session there 

 was some discussion on the problem of the determination of the specific 

 heat at high temperatures of the working fluid of the gas engine by 

 some more direct and, if possible, more continuous method than those 

 hitherto employed by members of the Committee, and the object of the 

 Note was to suggest a method which might fulfil these requirements. 



Note 37 deals with this problem also, and describes a method which 

 has been roughly tested by the authors and which appears to have 

 important possibilities. 



Note 38 is an account of an investigation on temperatures reached in 

 the cylinder of a small high-speed four-cycle engine using different 

 fuels, accompanied by a figure giving the results of the experiments. 



The Committee recommend that they be again reappointed, and ask 

 that a sum of 50/. be granted to them for the ensuing session. 



Stress Distributions in Engineering Materials. — Report of the 

 Committee, consisting of Professor J. Perky (Chairman), 

 Professors E. G. Coker and J. E. Petavel (Secretaries), 

 Professor A. Bare, Dr. C. Chree, Mr. Gilbert Cook, Pro- 

 fessor W. E. Dalby, Sir J. A. Ewing, Professor L. N. G. 

 FiLON, Messrs. A. E. Fulton and J. J, Guest, Professors 

 J. B. Henderson, F. C. Lea, and A. E. H. Love, Mr. W. 

 Mason, Sir Andrew Noble, Dr. F. Rogers, Mr. W. A. 

 ScoBLE, Dr. T. E. Stanton, Mr. C. E. Stromeyer, and Mr. 

 J. S. Wilson, to report on certain of the more Complex 

 Stress Distributions in Engineering Materials. 



The Eeport presented at the Australian Meeting of the British Asso- 

 ciation called attention to the desirability of obtaining complete and 

 systematic data with regard to three definite materials — namely, a mild 

 steel, an axle steel (carbon 0"3 per cent.), and a nickel steel alloy. The 

 Committee obtained a stock of one ton of mild steel early in 1914, but 

 owing to the outbreak of war further supplies of the other materials 

 are not yet available. The physical properties of the mild steel now in 

 the possession of the Committee have laeen the subject of several in- 

 vestigations, and a chemical analysis made at the National Physical 

 Laboratory has been furnished by Dr. Stanton as follows : 



C=0132 per cent. 

 Si = 0-028 „ 

 S=0-017 „ 

 P=0028 „ 

 Mn= 0-300 „ 



