TJIE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



MARCH 1845. 



XX. Is Capillary Attraction an Electric Phenomenon ? A 

 Memoir hy John William Draper, M.Z)., Professor of 

 Chemistry in the University of New York^. 



WRITERS on the mechanical theory of capillary attrac- 

 tion have contented themselves with the statement, 

 that the phasnomena exhibited by tubes of small diameter are 

 due to two causes, — the action of the tube upon the liquid, 

 and of the li(juid upon itself 



In our philosophical treatises capillary attraction is spoken 

 of as a force sui generis. It occupies an isolated position. 



But it appears to me, that without disturbing in any way 

 the characters which have been assumed for it as a specific 

 force, or the mathematical conditions under which it acts, there 

 is a point of view from which it may be regarded, which at 

 once brings it into an exceedingly interesting position. 



In this memoir I propose to show, — 



I. That the principal phaenomena ascribed to capillary at- 

 traction may be explained by regarding them as manifestations 

 of electrical action. 



II. That the voltaic battery has the power of controlling 

 the capillary relations of certain bodies. 



III. That, admitting the foregoing theory to be true, we 

 are able to explain several curious and obscure facts. 



I. (1.) If we take two pieces of flat glass, and press them 

 tightly together, they will adhere; and as the adhesion continues 

 in vacuo, the phaenomenon is explained by supposing they are 

 maintained in contact with one another by capillary attraction. 



But, if we draw them apart, and present them in succession 

 to a gold-leaf electrometer, we find they are both electrically 

 excited ; the one is positive, the other negative. By the well- 

 * Communicated by the Author. 



Phil. Mag. S. 3. Vol. 26. No. 172. March 184-5. O 



