126 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



this region tho Gnonpu.s itroceecled to Jiiakc continuous scries of observa- 

 tions along lines ot longitude 10' apart, with stations on each of these 

 lines 10 miles apart. Nine lines were run and four of tliese were 

 duplicated. Twelve to thirteen stations were made on each line, and 

 at each station the entire series of observations was rei)eated, thereby 

 resulting in the most thorough aiul comprehensive inquiry rcs])ecfing 

 such a body of water that had ever been ujulertaken up to that time. 

 The serial water temperatures were taken at the surface and at depths 

 of r>, 10, 15, 20, 25, 30, 40, 50, 75, 100, 150, 200, 250, 300, 400, and 500 

 fathoms, where the water was sulhcieutly deep, the loAver thermometers 

 being successively omitted as the water shoaled toward the coast, but 

 the distance between those that were used remaining always the saiiiie. 

 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 olf 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 wliich the distribution of the belts of cipuil tem- 

 perature may readily be shown. 



During the summer of 1800 the Fish Commission had the (joopera- 

 tion of the U. S. Coast Survey in continuing this inquiry, the superin- 

 tendent. Dr. T. C. IMendenhall, detailing for this purpose the steamer 

 Blah;, comnumded by Lieut. Charles E. Vreeland, U. S. Navy, whi(;h 

 remained in actual service from July 9 to August 4. The schooner 

 Grampus was at work upon the same ground from July 3 until August 

 25, and a party of observers was also stationed onboard the Nantucket 

 New South Shoal light-ship during the entire period of the investiga- 

 tion. Prof. Libbey was again in charge of the observations, aiul was 

 assisted by Prof. C. G. liockwtxxl, jr., Prof. M. I\rcNcill, Mr. S. T. Dodd, 

 Mr. L. S. Mudge, Dr. R. P. Bigelow, Mr. J. Zimmerman, Mr. W. II. 

 Dodd, and Mr. A. Harris. It was arranged to have three observers 

 each on the Grampus and the light-ship at all times, while oidy two 

 were necessary on thei^/«/i:e, as Lieut. Vreeland and his oflicers relieved 

 the civilians of many duties which would otherwise have devolved upon 

 them. The Fish Commission is under many obligations both to the 

 Light-llouse Board and to the Superintendent of the Coast Survey for 

 their liberal action in respect to this undertaking, and the assistance 

 rendered by them lias permitted a much more thorough and extensive 

 study of the problem than was possible in 1889. In acknowledging 

 the cooperation 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 tliose which bear upon the iislieries, and tlie Fish 

 Commission is, tlierefore, not alone concerned in the practical results to 

 be derived from their successful prosecution. 



