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CHARLES CHEEE: SOME PHENOMENA OF 



it differs somewhat conspicuously from that observed on quiet days. The principal or 

 only minimum for the day occurs on disturbed days in the early morning at 4 a.m. 

 in the inequality for the year but on quiet days it occurs at 11 a.m. or noon. The 

 difference is most readily grasped by reference to fig. 2. 



FiG.2. 



H 



tZOy 



Mid! 



Presumably there is a gradual transition in the type of the inequality in V as we 

 pass from the quietest to the most disturbed of days. It will, in fact, be noticed in 

 Table VIII. that the negative hourly values near 11 a.m. are numerically larger m 

 the inequalities derived from all the days than in those derived from the more highly 

 disturbed days, though earlier in the morning near the time of the minimum ^the 

 latter are much the larger. This doubtless represents the influence which on days 

 free from disturbance makes the minimum come at about 11 a.m. 



