Nichols and Franklin — Direction of Electric Current. 103 



depths below the level of 100 to 150 feet — as I state in the 

 article referred to, where I propose that deep borings should 

 be made, under government authority, on a sufficient scale to 

 settle the question. The borings have been made on Oahu ; 

 but, as I say above, the fossils of the reef -rock passed through 

 below the coral-growing limit have not been examined and the 

 subsidence therefore is not positively proved. There are many 

 collateral arguments in favor of the Pacific coral-island subsi- 

 dence reviewed in my paper which still remain strong; but 

 they may be held in abeyance until the borings have been sat- 

 isfactorily made. These and other points are discussed at 

 length in the paper to which I have above referred. 



I took no part in the controversy with reference to the state- 

 ments of the dogmatic Duke of Argyll, knowing that the 

 subject was in good hands. But I may here say that the 

 charge which he made that no one had dared to bring for- 

 ward and discuss the facts and views published by Mr. Murray 

 and others against Darwin's theory was the more inexcusable 

 that my paper had appeared as recently as in 1885 in the Lon- 

 don Philosophical Magazine. The charge was based on ignor- 

 ance of the facts on all sides, and on incapacity to appreciate 

 the spirit actuating men of true science. 



One other paper — on the question whether volcanic action is 

 a cause or not of trough-making over the Ocean's bottom, with 

 a review of the ocean's depths illustrated by a new bathymetric 

 chart — will close this series with the exception of the promised 

 paper on the rocks of the islands by E. S. Dana. 



Aet. XI. — An Experiment bearing upon the Question of 

 the Direction and Velocity of the Electric Current y* by 

 Edwaed L. Nichols and William S. Feanklin. 



[Contributions from the Physical Laboratory of Cornell University, No. III.] 



Ijst one of his recent articles in the Annalen der Physik und 

 Chemie, Ecepplf has described an. experiment in which the de- 

 flection of the galvanometer needle under the influence of 

 a stationary coil of wire carrying an electric current, was 

 compared with the deflection produced when the coil was 

 given a high velocity of rotation ; the axis of the coil being 

 the axis of revolution. If the current traversing the coil had 

 possessed direction and a finite velocity, a change in the de- 



* Eead before the American Association for the Advancement of Science ; 

 Cleveland meeting ; August, 1888. 



f A. Foeppl; Wiedemann's Annalen, Ed. 27, p. 410. 



