390 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
The following table, taken from the original record, illustrates the method of 
recording serial temperatures on board the Albatross. The observations followed a 
deep-sea sounding in which a depth of 2,022 fathoms was found, 42 minutes being 
re<iuired to complete it; 6 minutes were consumed in shifting the reels; 22 minutes 
in clamping the instruments to the temperature wire and veering 1,000 fathoms; 4 
minutes were allowed for the last of the series to take the temperature, and 16 minutes 
were required to reel in and detach the thermometers. 
Serial temperatures. 
Turns. 
Fathoms. 
M.aker’ s 
miiuber. 
Temiiera* 
turo. 
Correc- 
tion. 
Corrected 
tempera- 
ture. 
Remarks. 
946 
921 
74 
o 
0 
0 
74 
Apr. 18, 1891. 
Latitude 20° 47' 15" N. 
25 
69473 
65.4 
0 
65. 4 
896 
50 
54815 
59.3 
—0.3 
59 
Longitude 106° 15' 30" W. 
848 
100 
61755 
54. 6 
0 
54. 6 
Souiuliui^. 
754 
200 
69485 
50.2 
—0.4 
49.8 
A. in. 5 ii. 5m. i up 5 h. 47 m. 
659 
300 
60665 
45 
-0.2 
44.8 
Serial temperatures. 
565 
400 
63919 
42. 2 
0 
42. 2 
5 li. 53 m. ; down G li. 15 m. 
470 
500 
66724 
41 
HO. 1 
41. 1 
6 h. 19 Til. ; up 6 li. 35 m. 
377 
600 
63903 
40 
—0. 2 
39.8 
Time sounding, 42 m. 
281 
700 
69477 
38.8 
—0. 1 
3«. 7 
Serial temperat ures, 48 m. 
188 
800 
69480 
38 
-10. 1 
38. 1 
Total, 1 li, 30 m. 
94 
900 
51451 
37. 9 
—0. 3 
37. 6 
D. S. tlier. Negretti & Zamhra. 
Surface . . 
1, 000 
66735 
37.2 
—0.2 
37 
Fahr. scale. 
Bottom .. 
2, 022 
66735 
36 
0 
30 
H. C. F., recorder. 
The numbers in column of turns indicate where thermometers are to be attached 
to correspond to depths in column of fathoms. The serial temperature observations 
completed, the reels are changed again and the machine prepared for sounding. 
A HAUL OP THE TRAWL. 
The trawl follows sounding and serial temperatures in natural order, and while 
they were being taken the dredging boom would be rigged and topped up, the dredge 
roi^e shackled to trawl, and the latter hoisted to boom end in readiness to be swung out. 
Trawling and dredging are conducted by the commanding officer in person. He 
determines the direction in which the trawl will be laid out and dragged, and has the 
dredging boom rigged on what will be the weather or working side. In preparing 
to cast the trawl he is influenced in his choice of the working side by attendant 
conditions: 
1. It ia iieoeaaary that the dredge rope shall trend clear of the ship’s side while towing; hence 
the direction of the haul with reference to wind and current must he such that the vessel will either 
make a true course or drift to leeward away from the rope. 
2. He will follow the predetermined line of investigation as closely as ijracticahle, and whenever 
obliged to deviate from it will adopt a course that most nearly approximates to it. 
3. The most perplexing obstacle in the way of following a fixed line is often due to the contour 
of the sea bottom. It is difficult to trawl successfully down a steep slope; hence it becomes necessary 
to take the line of equal depths or to turn about and drag the trawl directly up the incline. 
4. The direction and force of wind and current with reference to the line of investigation and 
contour of the sea bottom bear directly upon the plan of operations and determine the working side 
upon which the dredging boom is to be rigged. 
The former practice of backing while casting the trawl and dragging it has been 
abandoned on account of the limited control the commander had over the course, which 
was always against the wind; for the natural tendency of a screw steamer is to bring 
