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After exhibiting this method, by which a wholly illiterate 
man might take and record the barometrical observations, 
Mr. Ward described a form of instrument that he had con- 
trived, which consisted of a simple tube of small bore, and 
of thin glass, which he had found rendered the boiling of 
mercury a comparatively easy operation, and to which need 
only be added a small bottle of mercury by way of a cistern, 
and a scale divided into twentieths of an inch, and which 
would be better done by comparison with a standard instru- 
ment than by actual measurement. The whole might then be 
protected by being inclosed in an iron tube, such as is used 
for gas. Such an instrument would be sufficient, and might, 
with a moderate demand, be probably supplied at a cheap 
rate, say from 10s. to 15s. 
Mr. T. D. Jeffcock inquired in what part of the pit it 
was proposed to place the barometer? 
Mr. Ward said that perhaps the best situation would be 
the place where the candles or lamps were kept, so that it 
might be seen by the men, and, if necessary, they might 
receive a caution before they began to work. He wished it 
to be understood that he was speaking of mines in which 
exposed lights might, under ordinary circumstances, be used. 
Where safety lamps were required, the barometer was of no 
use: every precaution was indispensable, and there might 
be danger, though not indicated by the barometer. 
In reply to another question by Mr. Jeffcock, 
Mr. Ward said it would not be necessary to have a 
barometer in every part of the pit where the men worked, 
as its object was not to indicate the amount of inflammable 
gas ; it was simply designed to show when the atmosphere 
was low, that being the time when most gas escaped from 
the goafs and fissures. 
The Chairman remarked that nearly all the explosions 
in the north had happened in a low state of the barometer 
