Measurements and Observations. 
169 
hour, when the load was taken off and the engine was run 
for one hour with no load. Then one-third load was suddenly 
put on and maintained for one hour, when the load was 
increased to half load, which was kept on for one hour, when 
full load was put on and maintained for one hour. The fuel 
used was anthracite, but -no measurement of the amount used 
was made. 
Friday , June 22. — The full load coke trial was made on 
this day and the first engine was started at 9 a.m. The time 
required to start the engine and get on full load was noted, 
after which each engine was run for nine hours on full load. 
On stopping the engine the fire was drawn and the unburnt 
fuel placed in iron vessels for weighing and examination. 
Saturday , June 23. — A- “novice” trial was made with 
three of the engines, namely, the National, the Campbell “ hit- 
and-miss,” and the 15 H.P. Crossley. The producers were got 
ready by each competitor to supply gas ; but the engine was 
twice started and the load put on by the observer who had 
had charge of the log sheet for that particular engine. Not the 
slightest difficulty was experienced in thus starting any of 
these engines. 
Measurements and Observations. 
The following is a description of some of the principal 
measurements and observations that were taken. 
Measurement of water used. — The water used by the 
scrubber and the vaporiser was measured by means of water 
meters lent by Messrs. Beck & Co., Ltd., which were of the 
positive type (Schonheyder’s patent), and a testing cock was 
placed on the delivery side. All the meters were carefully 
calibrated and found to be correct previous to the trials, and 
certain of them were again calibrated after the trials and 
were still correct. 
Indicator diagrams and the measurement of the I.H.P . — 
Indicator diagrams were taken at intervals and were studied as 
regards the initial and compression pressures, &c., but as no 
great reliance can be placed on indicator diagrams taken from 
gas engines as regards measurement of power 1 the I.H.P. 
was not determined and hence the brake efficiency, that is, 
the ratio of the B.H.P. to the I.H.P., was not obtained. Even 
if reliable diagrams could have been obtained the staff of 
observers was insufficient to take the necessary number of 
diagrams from each engine. Moreover, the indicator gear fitted 
to some of the engines consisted merely of a pin fixed to the 
end of the crank shaft and rotating with it. As is well 
1 This conclusion was come to by the Committee of the Institution of Civil 
Engineers on Internal Combustion Engines (see pp. 217 and 268, Min. Proc. 
Inst. C.E., Vol. CLXIII. 
