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bulletin: museum of comparative zoology. 



entire tide, ebb and flood. Bottom (30 fathom) readings were taken 

 hourly, for four hours, and then again after two hours, covering the 

 ebb, and the first of the flood. The results of these two sets are 

 given in full in the table, and the surface drift shown graphically in 

 Figure 40. The movements of the surface water off Nova Scotia are 

 greatly influenced by the wind (British Admiralty, 1903); hence the 

 value of current measurements depends largely upon the weather. 

 In the present instance, we were favored by a dead calm, preceded by 

 two days of light variable winds; hence the current may probably 

 be taken as normal for the time and place. 



The current at three fathoms was southeasterly at first; then 

 veered through south to southwest, which was its general course for 

 the major part of the flood; then shifted suddenly to the northeast 

 at the commencement of the ebb. During most of the set the velocity 

 was considerable, rising to nearly one knot per hour during the last 

 half of the flood. The general movement of water for the whole tide 

 (Fig. 40) was about four miles toward the southwest. 



The bottom current flowed toward the E N E during the ebb, 

 veering to the southwest at the beginning of the flood. Its flow was 

 much less rapid than the surface current, its maximum, at the strength 

 of the ebb, only .34 knot. The records are nOt sufRciently complete 

 to establish whether or not there was any dominant flow on the 

 bottom. But the fact that the direction of flow was practically uni- 

 form during the ebb, and that it was exactly reversed at the commence- 

 ment of the flood, suggests ^hat the dominant movement, if any, was 

 small. 



Current at 3 fathoms. Station 10231- July 27-28. ' High tide, Halifax, 

 11.40 A. M. High tide, Shelhurne, 12.26 P. M. 



(Directions are compass bearings (magnetic) from which current flows). 



July 27, P.M. 



