354 On the use of the Dynamic. Multiplier. 



lantic, that on entering upon soundings In the English Channel, he 

 has found an increase of temperature in the water of 2° Fahrenheit. 

 Those who differ from our views in regard to these currents, ought, 

 therefore, to propose some hypothesis which will account for the ex- 

 traordinarily low temperature of the waters which lave the Atlantic 

 coast of the United States. Were these waters derived as an eddy 

 current from the Gulf Stream, it is probable that they would no longer 

 serve for the myriads of codfish which now frequent our shores, and 

 which appear to inhabit the coldest waters. 



Many experiments upon the drift of currents have been made 

 with bottles containing memoranda of the date and locality in which 

 they were committed to the sea. These experiments are not with- 

 out their value, although it is obvious that a circuitous course is lia- 

 ble to be construed into a direct one, and that violent winds may 

 greatly affect the course of such objects upon the surface of the 

 ocean, while an important diversion may also result from a superfi- 

 cial cross current, as we have already noticed in the case of the Gulf 

 Stream. Perhaps the suspension of some suitable weight to these 

 floating messengers, with a line from five to twenty fathoms in length, 

 would afl'ord results of a more satisfactory character; although the du- 

 ration of such pendulous fixtures can hardly be relied on. If fitted in 

 this manner, the fact should be noted upon the memorandum inclosed, 

 which should specify also the length of line which may be attached. 



A full knowledge of the general system of currents in every ocean 

 is obviously of great value to the nautical profession, and is important, 

 also in its relations to physical science. It is hoped, therefore, that 

 these considerations will prove sufficient to stimulate our navigators to 

 make and record the necessary observations, and to promulgate the 

 same through the proper channels of information. 



Art. XX. — On the use of the Dynamic Multiplier,* with a new 

 accompanying apparatus ; by C. G. Page, M. D. 



The multiplier used in these investigations is composed of three 

 hundred and twenty feet of copper ribbon, one inch wide, wound 



* As the instrument in its generalized form as described in a previous No. of 

 this Journal, has become a very useful piece of apparatus, it is proper it should 

 have a name. As the phenomena exhibited by this instrument belong to the 

 class called Electro-dynamic, by Ampere, I have selected the term Dynamic Mul- 

 tiplier. 



