1ore than for : the number Seer amount to abou 
hree hundred. Ma any observations of ee i e, made 
not expressly, but soeiloibalig: | in Mines and caverns of thes 
countries, are omitted. They ssnsenlts relate to the tempe- 
rature of the air, and a8 results are analagous to those made 
more carefully elsewhere, 
tis necessary to mamas with much care experiments in 
a small way, when we mean to draw conclusions from them 
aflecting the heat ot Ste ngrens mass of the globe. spon 
or instance, the e one de in for e: 
one read anetrony. pare hundred and twenty-eight foet,) 
it would cause in the calculation an error of five hundred 
metres too near the surface in settling the depth at which 
water boils, 
‘“‘ With these precautions im view,” says M. Cordier, **] made 
experiments for myself, at the mine of Lattry, near Bayeux, De- 
partment of Calvados, where the shaft opens sixty metres above 
ae ‘evel of the sea: at the mine of Decise, to the north of the 
n of that name, in the Department of Ni ievre, elevated one 
hundred and fifty metres above the sea: at the mine of Ca 
at the Observatory at Paris. In the present memoir; tes centi~ 
grade division has been employed throughout.” 
M. Cordier kcal eniery into an elaborate investigasion of 
the sources of error, arising from the circulation of air from 
the bottom of the ; ae toward the top; from ine 
ture of the external air ; from the changes produced in the air 
by the infiltration of ree nto the mine from above; from 
the corrections required for the effect of candles, the pre- 
sence of workmen, and. the heat of their bodies and their 
In Pow and Mexico, Ann. de Chim. et de Phys. tom. 13, p. 207. 
The British phical f y 
for these twelve or fifteen years more, some are less exact. 
them liable to 
Most of jections, noted by ep Cooian , in’ the ss of the 
present re Led ‘all we Forming to the same conclusion, that the gl be of our 
always been, and now is, in 
ogre Wet 1. 15 
as % 
