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NOTES ON THE CREMORNE BORE. 461 
and Zambra, two of them kindly lent for the purpose by Mr. H. 
C. Russell, and being Kew-certificated. A fourth was a combined 
spirit and mercury thermometer registering both maximum and 
minimum temperatures by means of small steel pistons washered 
with vulcanite. 
The three overflow thermometers were placed with their bulbs 
uppermost to facilitate the breaking of the mercury column when 
the maximum temperature had been reached. Brass turnings 
were then packed around them in order that the heat might be 
conducted rapidly to their bulbs from the water in the bore. 
Strings were fastened to the bulbs to facilitate the withdrawal of 
the thermometers from the tube after the experiment of taking 
the temperature had been completed. The ends of these strings 
were carried close up to the top of the pipe, the brass turnings 
being packed around them like tamping around a fuse in a shot- 
hole. A few card-board wads and a layer of loose paper two 
inches in thickness were inserted in the upper portion of the tube 
to prevent the conduction downwards of the artificial heat, which 
would otherwise travel down to the thermometers from the upper 
end of the tube when it was dipped in the molten solder, previous 
to the upper cap-piece being ‘“‘sweated on.” <A ring-bolt for 
attaching the lowering cord was screwed into the upper cap-piece 
with molten solder sweated into it; and the whole cap-piece was 
then screwed and sweated on to the upper end of the tube in the 
same manner as the lower cap-piece. 
The tube carrying the thermometers was then lowered down 
the borehole by means of about five hundred feet of piano wire 
attached to two thousand five hundred feet of tarred rope. Owing 
however, to the fact that the bulbs of the two Kew thermometers 
(these two alone were used on the occasion of the first experiment) 
having a few thicknesses of soft paper around their bulbs it was 
found on raising the tube after it had remained near the bottom 
of the bore for about an hour, that no sensible alteration had 
taken place in the level of the mercury. Considerable delay 
however had occurred between the time that the thermometers 
