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MR E. M. WEDDERBURN ON THE TEMPERATURE SEICHE. 



August, during calm and variable winds. The rapidity with which the oscillation dies 

 down is rather remarkable. Perhaps a breeze which sprang up about 8 a.m. on 31st July 

 occurred in such a way as to kill down the existing oscillation almost entirely, without 

 being sufficiently strong to cause another series of oscillations. There is nothing note- 

 worthy in the fact that during the variable winds and calms from 1st to 5th August 

 no oscillations were started, as the winds were not strong enough or steady enough to 

 produce an alteration in the normal level (or a tilt) of the isotherms. Fig. 2 shows in 



METRES £ 



Fig. 2. 



rather a different manner and on a large scale the observations at Moritzfelde from 

 9th to 1 4th August. The relative positions of the isotherms are shown on this diagram, 

 and the most noteworthy fact is the bunching together of the surface isotherms after 

 the occurrence of the strong winds in August. This will be referred to later. 



§ 12. The observations in the Madiisee bear out fully all the generalisations made 

 from observations in Scottish lakes, and the views held by the Scottish observers do 

 not require modification in any important particular, although perhaps the statement 

 of them, which was put crudely to draw attention to important points, might be 

 bettered. Some misapprehension seems to have been caused by the statement that 

 when a temperature discontinuity has formed a lake acts as if it were divided into two 



