PHYSICAL OCEANOGRAPHY OE THE GULF OF MAINE 
799 
SALINITY IN AUTUMN AND EARLY WINTER 
Observations taken through September and October of 1915, in early November 
of 1916, and at the end of that month in 1912 afford a general picture of the salinity 
of the northern and western parts of the gulf at that season. Yachon (1918) and 
Mavor (1923) also give autumnal data for 1916, 1917, and 1919 for various localities 
in the Bay of Fundy region. 
In 1915 pairs of successive stations were occupied at intervals, expressly to show 
the seasonal changes, if any; and when the salinities for these are plotted an increase 
of 0.6 to 1.1 per mille is shown at the surface all along the coastwise belt east of Cape 
Elizabeth from July and August to October — an increase of about 0.5 to 0.9 per 
mille at the 50 to 60 meter level. At the same time, however, the vertical range of 
Fig. 160. — Vertical distribution of salinity off Gloucestor, August 31, 1915 (station 10306, dotted 
curve), October 1, 1915 (A, station 10324), and October 31, 1916 (B, station 10399) 
salinity decreased somewhat off Mount Desert (fig. 107) and off Machias, a changG 
foreshadowing the vertical equalization of the water that takes place in winter (p. 801) . 
A pair of stations for August 31 and October 1, 1915 (stations 10306 and 10324), 
show a corresponding increase of nearly 1 per mille in the salinity of the upper 40 
meters of water over the sink off Cape Ann at the mouth of Massachusetts Bay 
(fig. 160), though very little change took place at depths greater than 50 meters 
meantime, proving that the surrounding rim isolates its deeper strata of this bowl 
effectively in autumn as it does earlier in the season. 
The superficial stratum off the mouth of Massachusetts Bay also seems to have 
experienced some increase of salinity during the early autumn of 1916, the surface 
value being about 0.5 per mille higher at the station in question (10399) on October 
