ON GASEOUS EXPLOSIONS. Wit 
Gaseous Hxplosions.—Seventh Report of the Committee, con- 
sisting of Dr. DuGALD CLERK (Chairman), Professor DALBY 
(Secretary), and Professors W. A. Bonz, F. W. BURSTALL, 
H. L. CALLenpaR, E. G. Coker, H. B. Dixon, Drs. R. T. 
GLAZEBROOK and J. A, Harker, Colonel H. C. L. HoLpEn, 
Professors B. Hopkinson and J, EK, Preraven, Captain H. 
RiALL SANKEY, Professors A. SMITHELLS and W. WATSON, 
Mr. D. L. CHapman and Mr. H. E. WIMPERIS. 
Tue decease of the Chairman, Sir William Preece, was reported to the 
Committee in December last, when a letter of condolence was sent to 
the family. 
Sir William Preece had associated himself intimately with the 
investigations carried out by the Committee, and contributed an interest- 
ing Note on the Kinetic Theory of Gases. As Chairman he did much 
to help forward the important work on which the Committee is 
engaged both by his valuable suggestions and by his tactfulness and 
resource. His loss is not only deeply deplored, but felt to be a 
personal one by every member of the Committee. 
The Vice-Chairman, Dr. DucaupD CLERK, was unanimously elected 
Chairman. 
The Committee met three times during the session 1913-14 at the 
City and Guilds (Engineering) College, Exhibition Road, London, S.W. 
The following Notes were presented and discussed :— 
Note 82 by Professor Datpy on Suction Temperatures directly 
measured and deductions therefrom, together with a summary of a 
series of seventeen experiments made at the City and Guilds (Engineer- 
ing) College on a Crossley gas-engine with a cylinder seven inches in 
diameter, stroke fourteen inches, and with a compression ratio at 4’8. 
Note 33 by Mr. H. E. Wimpsris on Thermal Efficiency. 
Note 34 by Professor EK. G. Coker and Mr. W. A. ScosLE on 
Temperature Distribution in the Cylinder of a Gas-engine. 
Note 35 by Professor W. Warson on the Spectroscopic Study of 
the Combustion of Air-petrol Mixtures. 
The object of Note 32 was to show how the suction temperature 
varied with the speed, with the jacket temperature, and with the 
mixture. The records given in the Note relate to trials Nos. 72 to 90. 
The data were obtained by a research student of the City and Guilds 
(Engineering) College, Mr. Limbourne, working under the supervision 
of Professor Dalby. A table included in the Note shows the variation 
in the suction temperatures, and a set of curves, also included, gives 
the temperatures of the working mixture; these indicate how the direct 
knowledge of the suction temperature can be applied to determine the 
temperatures at other parts of the cycle. 
In Note 33 Mr. Wimperis discusses the thermal efficiency of an 
‘engine using as the working agent a standard gas referred to in the first 
1914. N 
