972 
BULLETIN OF THE BUREAU OF FISHERIES 
reproduced by the drifts of bottles that have crossed the southern side of the gulf 
from west toeast (p. 886), corroborating Huntsman’s (1923a, p. 18) conclusion that the 
dominant circulation in basins of this sort is kept in motion by the deep currents, 
not by the movements of the surface water. The clockwise drifts, which have been 
found to circle (or partly circle) several of the submerged banks (Georges, for 
instance (p. 974), and Nantucket Shoals), are also equally good evidence of dominance 
of the general circulatory scheme by the current flowing over the bottom, which the 
banks deflect just as islands would. 
SUMMARY OF THE HORIZONTAL, NONTIDAL CIRCULATION OF THE 
GULF OF MAINE 
The nontidal circulation of the Gulf of Maine (fig. 207) is essentially estuarine 
in type, as might have been expected from the contour of its bottom as well as from 
the trend of its coastline and from the large volume of fresh water discharged from 
the rivers tributary to it. The very considerable outflow from the gulf takes place 
at and near the surface— southward and westward past Nantucket Island and Shoals, 
in part, but in part as a clockwise movement circling around the eastern part of 
Georges Bank. 
The evidence marshaled in the preceding pages — measurements with current 
meters, drifts of bottles, temperatures, salinities, distribution of the plankton in the 
superficial waters, and dynamics — can be harmonized with one type of dominant 
circulation only — a general anticlockwise eddy around the basin of the gulf. 
The demonstration of this, named by Huntsman (1924) and by me the “Maine” or 
“Gulf of Maine” eddy, with all it implies in its biological bearing, is perhaps the 
most interesting result of the joint explorations of the gulf. 
The circulatory features most clearly established within the gulf are as follows: 
The eddying drift is operative throughout the year but differs in velocity, and 
generally in detail, from season to season. It is also complicated by subsidiary eddy- 
ing movements in the Bay of Fundy, Massachusetts Bay, Vineyard Sound, around 
Nantucket and Nantucket Shoals, and around and over Georges Bank, which are 
clockwise around these shoals but anticlockwise in the bays and basins, as Huntsman 
has shown to be the rule in northeastern American waters. 
In the late summer and early autumn, when our information is the most exten- 
sive (fig. 20?), the surface stratum of the inner part of the gulf eddies anticlockwise 
around an area of high density, the precise location of which shifts, from summer to 
summer, from the offing of the Bay of Fundy to a center in latitude about 43° to 43° 
30', 60 to 70 miles southerly from Mount Desert Island. 
The eastern side of the circling movement follows so definite a track northeast- 
ward and then northward, paralleling the coast of Nova Scotia, that at least 8 per 
cent of all the bottles yet put out in the gulf off Cape Ann and to the northward are 
known to have followed this route, no doubt with others not reported for one reason 
or another. The large number of bottles that have stranded on that coast shows a 
strong tendency inshore. This Nova Scotian side of the Gulf of Maine eddy also 
receives water in some volume from the dead zone off Cape Sable in summer, and 
in some years a westerly drift past Cape Sable into the gulf of Maine persists from 
spring through summer. 
