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violently forced out, with a noise, continuing for some time, 
which resembled the blowing off of an immense high-pressure 
steam-engine, and a violent discharge of gas, that extended 
over a distance of 640 yards in length, with an area of 
86,000 feet. At 400 yards from the point of issue it was 
met by one of the deputies. Though he drew down the 
wick of his lamp, the gas continued to burn for ten minutes, 
heating the wire red hot, and leaving the particles of coal 
attached to the wire gauze burnt quite red. At the end 
of the 640 yards, the gas burnt within the lamps of five 
men and boys there employed, until they extinguished them in 
a sump or pool at hand. There can be no doubt, therefore, 
that the explosive mixture extended still further. Where 
would the workmen on these occasions have been but for the 
lamp? 
A low state of the barometer is obviously favourable to 
the discharge of gas. Many practical men are aware of this. 
The most curious instance of its operation is that mentioned 
as occurring in a pit of Mr. Jobling's, of Jarrow, where, 
with a low barometer, inflammable gas was habitually noticed 
to issue from the coal; while, when the barometer was high, 
common air was observed to enter the coal at the very same 
fissures. But how many of those whose employment it is to 
inform the workmen when caution is requisite possess or 
understand a barometer? 
I was the more encouraged to bring forward this paper 
by finding, as I proceeded, that several circumstances then 
acquired an interest, in connection with others occurring 
elsewhere, which they by no means possessed while detached. 
But a cursory perusal of the accounts, by persons ever so 
well acquainted with the subject, would not exhibit these in 
their full force and bearing. 
I have attached to this paper some tables,* which include 
* The Diagrams on the wall contained these Tables, a little abbreviated. 
