[Footnote 217: This was given by a thermometer only placed in the cave at 7 P.M., and by construction not very sensible.]
[Footnote 218: The moment when the disturbance of the atmosphere commenced.]
[Footnote 219: M. Thury gives--462 C. as the minimum in the glaciere during the night in question; but on the next page he gives--68 C.
(=1976 F.). It is evident, from a comparison with other details of his observations, that the latter is the correct account.]