662 
BULLETIN OF THE BUREAU OF FISHERIES 
During the winter of 1919-20 the water of Gloucester Harbor (fig. 29) chilled 
to about — 1.5° and was colder than 0° from about January 12 to March 20; Booth- 
bay Harbor (fig. 30) chilled nearly to — 2° and was below 0° from January 5 to March 
5; Lubec Narrows (fig. 31), where tidal mixture with the water outside is more active, 
chilled to about the same temperature as Gloucester and was colder than zero 
for a slightly longer period — January 5 to March 20. In such situations, then, the 
strength of the tides and the frequency with which the water is renewed from out- 
side govern the minimum to which the temperature drops in winter more than the 
latitude does. 
THERMAL SUMMARIES 
Summaries of the thermal cyles for the following representative localities are 
given: (1) Mouth of Massachusetts Bay, off Gloucester; (2) the Fundy Deep, 
between Grand Manan and Nova Scotia; (3) near Mount Desert Island; and (4) 
the western side of the basin of the gulf in the offing of Cape Ann. 
1. MOUTH OF MASSACHUSETTS BAY, OFF GLOUCESTER 
Temperatures at various dates, to 0.1°, some by direct observation and others by interpolation 
Depth 
Mar. 1, 
1920 
20050 
Mar. 4, 
1913 
10054 
Mar. 19, 
1924 
Apr. 7, 
1925, Fish 
Hawk 
station 31 
Apr. 3, 
1913 
10055 
Apr. 9, 
1920 
20090 
May 4, 
1920 
20120 
Surface 
2.5 
2.9 
2. 2 
4. 1 
4. 1 
3.3 
6.4 
20 meters 
1.9 
2. 9 
1.9 
3.4 
4. 1 
2.5 
4.7 
40 meters 
1.9 
3.0 
1.8 
3.0 
4.0 
2.4 
4.3 
70 meters 
1. 7 
3.4 
1.8 
2.8 
4.0 
2.4 
2.7 
100 meters . 
1.5 
2.3 
Depth 
May 4, 
1915 
10266 
May 16, 
1920 
20124 
May 26, 
1915 
10279 
June 16- 
17, 1925 
Fish 
Hawk 
station 31 
July 10, 
1912 
10341 
July 19, 
1916 
10341 
Aug. 9, 
1913 
10087 
Surface 
6. 1 
9. 7 
10. 0 
12.9 
18. 3 
16.4 
16.7 
20 meters 
4.0 
5. 1 
7.2 
5.5 
9.0 
6.0 
10.4 
40 meters 
3.6 
2.9 
5. 2 
4.0 
6.6 
4. 1 
6. 7 
70 meters 
3. 6 
2. 8 
3.8 
3.6 
4.6 
3.7 
6.3 
100 meters 
3.6 
2.7 
4.6 
5.2 
Depth 
Aug. 22, 
1914 
10253 
Aug. 22, 
1922 
10632 
Aug. 22, 
1922 
10633 
Aug. 31, 
1915 
10306 
Sept. 29, 
1915 
10320 
Oct. 1, 
1915 
10324 
Oct. 27, 
1915 
10339 
Surface 
18.9 
18. 00 
18.7 
16. 1 
10.5 
10.3 
10.8 
20 meters . 
12.0 
9. 10 
12.3 
12.0 
10. 6 
10.0 
6.5 
7. 40 
4. 70 
7.0 
8. 3 
10. 1 
9.0 
70 meters 
5.3 
6. 7 
7.0 
7.5 
7.3 
100 meters 
4.6 
6.0 
7.1 
Depth 
Oct. 31, 
1916 
10399 
Nov. 20, 
1912 
10047 
Dec. 4, 
1912 
10048 
Dec. 23, 
1912 
10049 
Dec. 29, 
1920 
10489 
Jan. 16, 
1913 
10050 
Feb. 9, 
1921 
10504 
Feb. 13, 
1913 
10053 
Surface _ 
10.0 
9.2 
8. 1 
6. 9 
5. 6 
5.4 
3.3 
2.8 
20 meters 
9. 6 
9. 0 
7.8 
6. 9 
6. 0 
6.4 
3. 5 
2.8 
40 meters 
8.2 
9.0 
7.8 
6.9 
6.9 
5.3 
3.6 
2.8 
70 meters 
6. 1 
7.8 
6.9 
6.9 
5.6 
3.0 
l'OO meters 
6.4 
7.0 
