EEPOPiT 



RECENT PROGRESS IN PHYSICS, 



BY Dr. JOH. MUnLEU, 



PROFESSOR OF PHYSICS AND TECHNOLOGY IN THE UNIVERSITY OF FREIBURG. 



[Ti'anslated from tlie German for the Smithsonian Institution.] 



It is a part of the original plan of organization of the Institution to 

 furnish occasional reports on the progress of special branches of knowl- 

 edge, and in accordance with this the following report has been trans- 

 lated from the German, in which it was written. 



It relates to a branch of science which, perhaps, more than any 

 other, is in the process of practical application to economical purposes, 

 and is principally composed of materials not accessible to the English 

 reader. The original article is by Professor Miiller, the celebrated 

 German physicist. The translation was made by the late Woods 

 Baker, Esq., of the Coast Survey, whose untimely death, science has 

 been called to mourn. 



We are indebted to Vieveg & Son for the wood-cuts, who have lib- 

 erally furnished us with copies of the original at the cost merely of 

 the metal and the casting. 



A second portion of the work will be published in the appendix to 

 the next annual report of the Regents, and so on until the whole is 

 completed. The present portion will be found particularly valuable 

 in relation to the construction and use of galvanic batteries. 



The report pre-supposes sucli a preliminary knowledge of the sub- 

 ject as may be obtained from the elementary books used in our schools ; 

 and in order to render some of the passages of the text more easily 

 understood, a few notes have been added at the end. The rapidity 

 with which government work is printed does not allow the additions 

 or corrections to be inserted on the proper page, and hence in study- 

 ing the article the notes should be examined first to ascertain the part 

 of the text to which they belong. 



GALVANIS:\I. 



SECTION FIRST. 

 THE CHEMICAL AND CONTACT THEORIES. 



Introduction. — [The author commences his report on the recent pro- 

 gress of galvanism with a brief account of the discussions which have 



