GASEOUS EXPLOSIONS. 167 
devoted to research. Professor Dalby is working on a scheme with 
Dr. Dugald Clerk for equipping one bay with internal-combustion 
engines. It is recognised that the Imperial College would be materially 
assisted in carrying out their ideals if the work of the Committee were 
concentrated in the new laboratories. 
Owing to a delay in the completion of the laboratories it is not 
possible to present a report this year. Work, however, has been 
carried on with the old plant by Professor Dalby with the aid of a 
research scholar, and some important results have been obtained which 
will be communicated in due course. The general work of the Com- 
mittee has also gone steadily on during the year. 
Three meetings have been held at the City and Guilds (Engineering) 
College, at which the following Notes were presented and discussed :— 
Note 26. ‘ The flow of heat from a charge of air subject to cyclical 
variations of state in the cylinder of a gas engine,’ 
and 
‘The comparison of the temperature readings of a plati- 
num thermometer with the temperature computed from 
the pressure volume diagram.’ By Professor Dalby. 
Note 27. ‘ The flow of heat between a charge of air enclosed in a 
gas-engine cylinder and the walls of the cylinder when 
the charge is subjected to a cyclical variation of tem- 
perature.’ By Professor Dalby. 
Note 28. ‘ Leakage of charge.’ By Professor Dalby. 
Note 29. ‘ Gas-engine temperatures.’ By Professor Hopkinson. 
Note 30. ‘ The effect of compression ratio on the efficiency of a 
gas engine.’ By Professors G. Asakawa and J. E. 
Petavel. 
Note 31. ‘ Determination of leakage by the method of alternate 
compression and expansion.’ By Dugald Clerk. 
Note 26.—In this Note, which was presented last year, Professor 
Dalby drew attention to a method of testing and correcting for leakage 
in a gas-engine cylinder. A detailed explanation of this method was 
given in the note, which was accompanied by eight photographic records 
relating to the experiments referred to; these were carried out at one 
constant speed. The observations were made by two research students 
of the Imperial College—Messrs. Mawson and Begg—working under 
the direction of Professor Dalby. 
Note 27. This Note is a record of the results obtained by applying 
the method to the same engine run at different speeds in order to 
ascertain the effect of speed on the leakage. The paper was accom- 
panied by eleven large blue prints giving the data and the deductions 
drawn from them. 
Note 28. There was considerable discussion at the Committee 
regarding the amount of leakage found, and at the request of the 
Committee Professor Dalby made some further experiments, the results 
of which are embodied in Note 28. This Note was accompanied by a 
blue print of two curves and a photographic record. 
Note 29. Professor Hopkinson’s Note consisted of general remarks 
relating to the importance of knowing the suction temperature and its 
influence on the heat flow. 
