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Award of the Judges. 
[Text continued from page 176.] 
alone open is very noticeable, as are also the two compression 
lines. 
An interesting set of Mathot diagrams was obtained from 
the National and from the Campbell “hit-and-miss” engine 
whilst the engines were starting. The first few explosion strokes 
showed gas of good quality, but soon the maximum pressure 
dropped to a very low figure showing poor gas. This effect 
lasted for about one minute and a half when the gas began 
to improve in quality, and in three minutes from the start it 
was satisfactory and the full maximum pressure required was 
obtained. A Mathot card taken from the Davey-Paxman 
engine showed very clearly the effect of altering the timing 
of the ignition, which could readily be done with the timing 
arrangement fitted to this engine. 
There is no doubt that the Mathot diagrams are invaluable 
in the case of gas engines, as they enable the Engineer to feel, 
so to speak, the pulse of the engine. 
Award of the Judges. 
After full consideration of the observations recorded the 
Judges arrived at the conclusion that the two plants which 
most satisfactorily fulfilled the regulations and commended 
themselves most for general purposes were the 20 B.H.P. plant 
exhibited by the National Gas Engine Company, Ltd., and the 
15 B.H.P. plant exhibited by Messrs. Crossley Bros., Ltd. 
In order to discriminate between these two, a detailed 
examination was made of forty items, each of which was 
separately considered and marked, with the final result that 
the following award was made : — 
Gold Medal to the National Gas Engine Company, Ltd., Wellington 
Works, Ashton-under- Lyne, for their 20 B.H.P. National Gas Engine, 
with 20 B.H.P. National Suction Gas Plant. Catalogue, No. 7. 
Silver Medal to Messrs. Crossley, Bros., Ltd., Openshaw, Manchester, 
for their 15 B.H.P. gas engine and 15 B.H.P. Suction Gas Producer. 
Catalogue, No. 31. 
General Conclusions. 
It is evident from the results of the trials, that many of 
the suction gas producer plants submitted for trial were quite 
satisfactory. There can be no reasonable doubt that with due 
care any of them would give satisfaction if employed for agri- 
cultural work as an “ estate ” engine. Although, however, less 
manual labour is required than in the case of a steam engine, 
more intelligent care is necessary to ensure the production of 
gas of good quality. 
The economy trials confirm the results that have been 
previously obtained elsewhere, when the fuel required for 
banking and starting is taken into account. As regards the 
