PHYSICAL OCEAN OGBAPH Y OF THE GULF OF MAINE 
659 
water that had been cooled near shore moving out from the land and at the same 
time sinking, to develop a shelflike intrusion into the warmer water of the center of 
the bay. The profiles also suggest that the coldest water was produced even closer 
in to the coast line than the innermost of the two stations, and that the whole column 
was colder than 0° next this sector of the coast at about the end of January, down 
to a depth of 10 to 15 meters. 
In 1925 the southern side of Massachusetts Bay had experienced its mini- 
mum temperature for the winter and had commenced to warm again by the last 
week in February, when the mean temperature of the surface (1.65°) was nearly 1° 
higher than it had been two weeks earlier, with a corresponding rise in mean bottom 
IS S>r<ATions 
Fig. 84. — Temperature profile running from the Marshfield shore out into Massachusetts Bay, February 6, 7, and 27, 1925. 
The broken curve is the isotherm for 2° on February 24 
temperature from 0.95° to 1.68°. On the 24th the whole surface of the bay was 
close to 2° in temperature, a regional uniformity illustrated by readings of 2.2° a mile 
or two off Gloucester, in the one side of the bay, with 2° to 2.1° in the central parts 
and 2.3° near Provincetown (station 5) in the other side. The offshore drift of water, 
chilled next the Plymouth shore, had also slackened, if not entirely ceased (fig. 84). 
The vertical distribution of temperature off Provincetown (Fish Hawk station 5) 
on February 24 is interesting because the bottom reading was the highest (2.34°) 
recorded for any level at any of these late February stations. A 40-meter salinity 
of about 33 per mille at 40 meters there, contrasted with 32.7 to 32.8 per mille in the 
central part of the bay, shows that some inflow through the bottom of the channel 
