BurbanTc — Apparent Variations of the Vertical. 331 



does not appear to be any consistent relation between the tilting 

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showing some extreme examples of this tilting effect during 

 cold winter days, Jan. 29th-Feb. 9, 1908; and also the less 

 marked effect during mild weather, in April and May. 



The pronounced tilting during the period Jan. 29-reb. 9, 



