72 National Geographic Magazine. 



instruments in the hands of experts, will produce far superior re- 

 sults at a much less cost than was possible at the time the Survey- 

 was inaugurated. 



The charting of the great ocean currents, has long been an 

 interesting investigation to hydrographers the world over, A 

 sketch of the efforts, projects, and devices that have been resorted 

 to by the Coast Survey in the attempt to unravel the mysteries of 

 the Gulf Stream, would exemplify the continuous demand for 

 improvement and new exertions under which those employed 

 upon the work have always labored, although the full measure of 

 knowledge sought has not yet been obtained. But it is not neces- 

 sary to enter into these details at this time ; let it suffice that 

 many experiments and failures pointed out the path to be fol- 

 lowed by subsequent observers, and stimulated to new efforts,. 

 until at last appliances have been perfected that have already 

 produced wonders, and it is safe to predict, will ere many years 

 show the ocean currents on the charts of the world with the same 

 relative precision that the currents in a river or harbor can now 

 be indicated. Lieutenant Maury gave us current charts that 

 were a marvel in their day, but his information, or data, was 

 defective, and his conclusions, therefore, only approximate ; and 

 how to improve on the data he had, has ever since been the sub- 

 ject of research. The depth of the ocean is necessarily an im- 

 portant factor in the study of its features, as erroneous depths 

 lead to false hypotheses. The introduction by the English of a 

 method of sounding with a wire, has therefore proved an im- 

 portant advance. American officers have perfected the apparatus 

 and severely tested the methods, demonstrating the reliability of 

 the results and the total unreliability of the old deep sea sound- 

 ings taken with a line. These accurate wire soundings have re- 

 vealed new facts, disproved old theories and formed new ones to 

 guide future researches. So successful is the improved apparatus 

 that specimens of the bottom of the ocean have been brought up 

 from a depth of five miles. The great value of this system, how- 

 ever, is not confined to the mere ascertainment of depths for the 

 hydrographer and cartogi-apher, as may be readily demonstrated 

 by referring to the reports of the Fish Commissioner. A further 

 step towards improving on Maury's results ; the crowning glory 

 that is to shed light on much that has been dark, and trace out 

 those ocean currents we have heretofore vainly endeavored to fol- 

 low, is found in the invention and devices of a naval officer 



