126 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
this region the Grampus proceeded to make continuous series of observa- 
tions along lines of longitude 10’ apart, with stations on each of these 
lines 10 miles apart. Nine lines were run and four of these were 
duplicated. Twelve to thirteen stations were made on each line, and 
at each station the entire series of observations was repeated, thereby 
resulting in the most thorough and comprehensive inquiry respecting 
such a body of water that had ever been undertaken up to that time. 
The serial water temperatures were taken at the surface and at depths 
of 5, 10, 15, 20, 25, 30, 40, 50, 75, 100, 150, 200, 250, 300, 400, and 500 
fathoms, where the water was sufficiently deep, the lower thermometers 
being successively omitted as the water shoaled toward the coast, but 
the distance between those that were used remaining always the same. 
The density of the water was also ascertained at the surface and bot- 
tom, and at one intermediate position in deep water. It will be ob- 
served that, by this means, the physical conditions of the waters of 
this region were determined along parallel sections running off from 
the coast into the warm water bordering the inner edge of the Gulf 
Stream, and the results can, therefore, be graphically represented by 
means of profiles, on which the distribution of the belts of equal tem- 
perature may readily be shown. 
During the summer of 1896 the Fish Commission had the codpera- 
tion of the U. S. Coast Survey in continuing this inquiry, the superin- 
tendent, Dr. T. C. Mendenhall, detailing for this purpose the steamer 
Blake, commanded by Lieut. Charles E. Vreeland, U. S. Navy, which 
remained in actual service from July 9 to August 4. The schooner 
Grampus was at work upon the same ground from July 35 until August 
25, and a party of observers was also stationed on board the Nantucket 
New South Shoal light-ship during the entire period of the investiga- 
tion. Prof. Libbey was again in charge of the observations, and was 
assisted by Prof. C.G. Rockwood, jr., Prof. M. McNeill, Mr. 8. T. Dodd, 
Mr. L. S. Mudge, Dr. R. P. Bigelow, Mr. J. Zimmerman, Mr. W. H. 
Dodd, and Mr. A. Harris. It was arranged to have three observers 
each on the Grampus and the light-ship at all times, while only two 
were necessary on the Blake, as Lieut. Vreeland and his officers relieved 
the civilians of many duties which would otherwise have devolved upon | 
them. The Fish Commission is under many obligations both to the 
Light-House Board and to the Superintendent of the Coast Survey for 
their liberal action in respect to this undertaking, and the assistance 
rendered by them has permitted a much more thorough and extensive 
study of the problem than was possible in 1889. In acknowledging 
the codperation of these Bureaus it is also well to note that these 
physical studies will probably be as significant in regard to questions - 
of navigation as to those which bear upon the fisheries, and the Fish 
Commission is, therefore, not alone concerned in the practical results to 
be derived from their successful prosecution. 
a 
belts, de 
