[ 231 ] 

 XXVII. Intelligence and Miscellatieous Articles, 



EXPLANATORY FACTS. BY MR. STURGEON, LECTURER ON EX- 

 PERIMENTAL PHILOSOPHY AT THE HONOURABLE EAST INDIA 

 company's ACADEMY, ADDISCOMBE. 



PERHAPS a more disagreeable task could hardly fall to the lot 

 of any individual than that of having to rescue from the un- 

 warrantable attack of another, that which is justly and honestly his 

 own right. And it is more particularly so, when the claim is either 

 of a literary or a scientific character, where credit alone is but too 

 generally the humble reward of much industry, anxiety, expendi- 

 ture of money, time, &c. 



I am, at present, however, placed in that unpleasant situation, 

 and have no means so likely for redress as that of placing a few 

 facts before the scientific part of the readers of the Philosophical 

 Magazine. 



By referring to the Number for November last, it will be seen 

 that I had, some time previously, succeeded in producing electro- 

 dynamic phenomena, of various classes, by giving to magnetically 

 excited electric currents one uniform direction through the ter- 

 minal conducting wires, by means of a certain contrivance which 

 may very properly be called the Unio- directive Discharger; because 

 it has the power of uniting, and discharging, in any one direction 

 those currents which, in consequence of the mode of excitation, 

 are originally urged, alternately, in directions opposite to each 

 other. 



Without some arrangement for this purpose, every magnetic 

 electrometer in which coils of wire form the original source, would 

 have remained comparatively useless ; and those phenomena, the 

 most interesting in electro-dynamics, could never have been pro- 

 duced by the opposing currents, however powerful, rushing from 

 these copious sources of electric action. 



To exhibit the spark, heat wires, or to produce the shock, it 

 matters not in which direction the current flows, nor whether it re- 

 ciprocates, or proceeds in one uniform direction. 



Electro-magnetic phaenomena may also be exhibited by recipro- 

 cating currents, or even by opposing currents, provided the force 

 in one direction sufficiently predominates over that in the other. 

 But in the production of chemical decomposition, with exact polar 

 arrangement of the liberated constituents, it requires that the elec- 

 tric currents be not of a reciprocating character. 



It is, moreover, a particular object of the experimenter, in every 

 electro-dynamic process, to avail himself of as much as possible of 

 excited electric force ; and also to prevent, as far as he can, the 

 existence of any counteraction whatever. 



Now, in well-constructed magnetic electrometers, the recipro- 

 cating currents are nearly of equal force, and the predominancy, if 

 any there be, can never be calculated on as a disposable force, 

 either as regards degree or direction. 



