J^ ON THB VOLTAIC BATTER V#. 



plates only arc employed. "Every practical electrician wonld. 

 however, I am convinced, refer the anomalous results of 

 these experiments to some inaccuracy in the apparatus, or 

 to a difference in the density of the fluid with which the 

 batteries were charged ; as the irregularities obtained were 

 by far too considerable, to have been produced by a differ- 

 ence so trivial os that existing between the number of plates 

 employed on this occasion. The authority of a philoso** 

 pher, so highly and so justly celebrated as Dr. Davy, may 

 give extensive and respectable circulation to even palpabU? 

 errours; it is therefore the imperative duty of every genuine 

 friend of science, to exuminfe Assertions flowing from such 

 a source, and to give to the public any facts he may be 

 acquainted with, that militate against, or contradict them. 

 Experiments As early as the y^ar 1904, dirCct experiments were made 



on the subject ^^ ascertain the duantity of wirei ignited by different iium- 



made some . 7^ \- t Vv -r^ 



years ago. d^*"^ of pmteS. Of tnts! I presume Dr. Davy v^as not aware, 



when hd stated, that ** the inquiry hdd not yet been touched 

 cnf* he may not have read the 18th tolurae of the Philo- 

 •ophical Magazine, or the 7th and 8th volume of Mr, 

 Nicholson's Journal, or Cuthbertson's Practical Electricity, 

 ■where an account of these experiments is published. lit 

 the 7tlj volume of this Journal, page 207, a series of expe- 

 riments with large batteries of plates of 4 inches, and of 

 Thepow^^of 8 inches square, is detailed by Dr. Wilkinson : the results 

 J"'*^^" *.^ ^^ of these experiments prove, that the power of ignition in" 

 the places. creases in direct proportion to the number of plates employed; 

 and this law «f increase is uniform, whatever be the size of 

 the plates. If a battery of any given size melt any deter- 

 minate length of wire, two such batteries will melt twice 

 the length, three iuch batteries will treble the effect, and 

 by four it will be quadrupled^ provided the acid with which 

 they are charged is of equal strength. 

 Other experi- In the 8th volume of this Journal, pnges 97 and 205, » 

 meats gave si* yg,.„ accurate series of experiments is given bv Mr. Cuth- 

 «ilar result*, ^ _ n-,i ii.,7 



bertson. By a variety ot trials he proves, that double the 



quantity of plates burns twice the length of wire; and he 

 points this out as a distinction between the action of com- 

 mon and Voltaic electricity, but concludes, that the dif- 

 i#rtnc<i arises from the imperfection »f the Voltaic appara- 

 tus ; 



