RESULTANT OF CURRENTS AND VIBRATIONS. 87 



demonstration. Hold vertically two parallel sheets 

 of paper, while blowing a current of air from the 

 mouth between them. The current changes a 

 part of the atmospheric vibrations at right angles 

 with the inner surfaces of the sheets of paper to a 

 corresponding current parallel with their adjacent 

 surfaces, and thus partially neutralizes their action. 

 The vibrations against the outer sides of the sheets 

 of paper, relieved of counteracting force, predom- 

 inate, and propel the two sheets toward each other ; 

 producing a resultant movement by the combined 

 action of the vibrations without, and a current be- 

 tween them. 



A similar resultant movement of two bodies 

 takes place, by converting the vibrations of the 

 electric ether between their adjacent sides into 

 currents, as described in Chapter XII.; whereby 

 resultant movements of two parallel conducting 

 wires are produced reciprocally toward each other, 

 at right angles to the direction of the currents 

 through them, exhibiting the phenomenon of 

 Attraction. 



When two surfaces are thoroughly in contact, as 

 of glutinous, or homogeneous bodies, the vibrations 

 and currents between their inner surfaces cease, 

 leaving the vibrations against their outer surfaces 

 to predominate ; holding them together, and pro- 

 ducing the phenomena of Adhesion and Cohesion. 



The orbital revolutions of the planets transmit 

 vibrations on a sublime scale through the electric 



