BIGELOW: OCEANOGRAPHY OF MASSACHUSETTS BAY. 



387 



sity, for November 20, at the temperature in situ, disregarding pres- 

 sure, was 25.24 at the surface, 25.27 at the bottom; i. e., the vertical 

 stabihty of the water was so sUght that all that would be necessary to 



BVTH 



Fig. 1. — Temperatiire sections ofif Cape Am, November 20 (Station 10,047) ; 

 December 4 (Station 10,048) ; December 23 (Station 10,049) ; January 16 

 (Station 10,050) ; Februarj- 13 (Station 10,053) ; Marcli 4 (Station 10,054) ; 

 Marcli 19 (Stations 1 and 2, W. W. Welsh) ; April 3 (Station 10,055) ; and 

 off Gloucester Harbor, April 14 (Station 10,056) and May 17 (Station 32 

 W. W. Welsh). 



cause a reversal of density, with consequent vertical circulation, 

 would be a cooling at the surface of about 1°. Evidently then, 

 dynamic overturning of the w'ater might be expected to be active from 

 this time onward as the surface became colder and colder with the 



