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him that the steam jet principle cannot be advantageously 
employed to any considerable extent for the ventilation of 
coal mines, he respectfully declines that honour, and prefers 
giving a brief account of what little he has done in the 
matter, so far as it appears to him at all likely to be useful 
to others, which he trusts will be received as a substitute for 
a paper. 
The manner in which the ventilation was effected in the 
pumping shaft above referred to, may be described as follows : 
The shaft, as before stated, is 120 yards deep, and the 
pump is divided into two lifts ; the lowermost lift is effected 
by means of a working barrel and bucket of ordinary 
construction, situated a few feet from the bottom of the 
pit, which delivers the water into a cistern about midway 
up the shaft. The upper lift is effected by a ram or plunger 
working immediately above the cistern from which it draws 
the water, and forces it up a main of seven inches cast iron 
pipes, which reach the top of the shaft where the water is 
delivered into an open reservoir. Near to the top of the 
seven inch main a temporary connection was made with 
another pipe of the same diameter, and nine feet long, placed 
vertically ; and into the lower part of this pipe was 
conveyed a piece of f inch common gas pipe, with its 
end turned upwards, the other end of the gas pipe 
being connected to the steam boiler, close at hand, by means 
of a stop-cock. This simple arrangement constituted a most 
perfect ventilating apparatus, the effect of which appeared 
rather extraordinary. The quantity of steam passed up the 
interior of the seven inches pipe, from the jet piece, was regu- 
lated at pleasure, by means of the stop-cock near the boiler ; 
and thus the ventilating power of the jet could be increased or 
diminished to any desired extent. 
It should be remarked that the workmen had partially 
removed the clack-door at the bottom of the rising main 
