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were, in fact, not observed there, which is additional evidence of the nature 
of the temperature changes. It was unfortunate that more continuous 
observations were not made at the ends of the lake, but the difficulty of 
observing day and night, with only two observers, in an open boat, and 
usually in pouring rain, was great. From the point of view of the tempera- 
ture seiche it was unfortunate that most of the observations were made at 
the centre of the lake, but I was anxious to observe in as deep water as 
possible so as to follow the bottom temperature changes. It was intended 
by observing at both ends of the lake to show opposition in phase at the 
two ends, but the loss of a thermometer at the beginning of this series of 
