560 



BULLETIN OF THE BUREAU OF FISHERIES 



its flow must then have slackened (or its temperature have risen), because the surface 

 temperature of the critical locality rose to 4.6° by April 2S and to 7.8° on May 29, 

 though the whole column of water on German Bank was still only 2.7° and 4.2°, 

 respectively, on these dates (ice patrol stations 3, 21, 22, 37, and 38, p. 997). The 

 seasonal time-table seems to have been about the same in 1915, when the cold Nova 

 Scotian water was responsible for a temperature of about 3° from German Bank 

 out across the eastern side of the basin on May 6 to 7 (fig. 27), suggesting that the 



i/v/y Aup- 'Sepf. Oc^. /Vov. Dec. Jan. feA. /Varc/h /{pr /^ay June 



Fig. 29.— Mean nir temperature (solid curve) and water temperature (broken curve) for 10-day intervals at Ten Pound 

 Island, Gloucester Harbor, Mass., from July 1, 1919, to June 30, 1920 



inrush into the gulf had reached its head some time in late March or April of that 

 year. In 1920, however, it is certain that the cold current did not begin to flood 

 past Cape Sable into the gulf in any considerable volume until after the middle 

 of April. 



Water as cold as 0.27° to 0.56° had, it is true, spread westward past La Have 

 Bank to within a few miles of the longitude of Cape Sable as early as the 19th of March, 



