

1835.] Philosophical Transactions for 1.834. 229 



On the functions of some parts of the Brain. By Sir Charles Bell 



On the repulsive power of Heat. By the Rev. B. Powell. 



On the equilibrium of a mass of Homogeneous Fluid at liberty. 

 By James Ivory, Esq. 



Observations on Torpedo. By John Davy, M. D. 



Remarks in reply to Dr. Daubeny on the air disengaged from the 

 recent Volcano. By John Davy, M. D. 



On the ova of the Ornithorynchus Paradoxus. By R. Owen, Esq. 



Observations on the motions of Shingle Beaches. By H. R. Pal- 

 mer, Esq. 



Analysis of the Moira Brine Spring. By A. Ure, M. D. 



Experiments on the Velocity of Electricity, &c. By C. Wheat- 

 stone, Esq. 



Electricity. — Mr. Harris for the purpose of prosecuting his re- 

 searches invented a new electrometer, by the medium of which he 

 has observed two new laws. 1 . A given quantity divided upon two 

 perfectly similar conductors, was found to exert upon external bodies 

 only a fourth part of the attractive force apparent when disposed upon 

 one of them. 2. When divided upon three perfectly similar con- 

 ductors, the force upon either is only one ninth of the force apparent 

 when disposed upon one of them, and so on ; that is, the quantity 

 being constant, the force is as the square of the surface inversely, or 

 the surface being constant as the square of the quantity directly. 

 These are illustrated by the following experiment : 



Three or four perfectly similar and equal conductors of a cylindri- 

 cal form being well insulated, a given quantity of electricity was 

 communicated to one of them by means of a charged jar, and the at- 

 tractive force measured by the electrometer. The electrified bodies 

 being now reduced to a neutral state, a second equal quantity was 

 again communicated to the same conductor as before, after which it 

 was caused to touch one of the others so as to divide the charge on 

 both. Each conductor was observed to be equally charged ; the force 

 however after making the requisite correction for distance between 

 the attracting bodies amounted only to one fourth of the previous 

 force. The results are represented in the following table : 



Comparative quantity. 



l . . . 

 J . . . 

 i . . . 



i • • • 



2. The author distinguishes three elements peculiar to the condi- 

 tions of electrical accumulation. 1. The comparative quantity actu- 

 ally accumulated. 2. The quantity not sensible to the electrometer. 

 3. The quantity appreciable by the electrometer. 



3. It was supposed by Mr. Singer, that the diminished intensity 

 observable in disposing a given quantity of electricity, is altogether 

 referable to the attractive force of the atmosphere,to the influence of 

 which the electric particles become more extensively exposed ; but 

 this hypothesis is not corroborated by the experiments of Mr. Harris 



