THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



+ 



[FOURTH SERIES.] 



AUGUST 1867. 



XI. Experimental Researches in Magnetism and Electricity. 

 By H. Wilde, Esq.* 



[With a Plate.] 



§ 1 . On some new and paradoxical Phenomena in Electro-magnetic 

 Induction, and their relation to the Principle of the Conserva- 

 tion of Physical Force. 

 1. r I^HE principle of the conservation of force, as I apprehend 

 A it, is the definite quantitative relation existing between 

 all the phenomena of the universe whatsoever, both in direction 

 and amount, whether such phenomena be considered in the rela- 

 tion of cause and effect, or as antecedent and consequent events. 

 2. In the particular application of this principle to the ad- 

 vancement of physical science, and also to the invention of new 

 engines and machinery to meet the progressive requirements of 

 society, problems not unfrequently present themselves which 

 involve the consideration of static and dynamic force from 

 several different aspects ; and the solution of these problems 

 often brings out results which are as surprising as they are 

 paradoxical. Of such cases, in which the idea of paradox 

 alluded to is involved, may be mentioned the one contained in 

 the 36th Proposition of Newton's Principia (Book 2, Cor. 2)f, 

 and in D. Bernoulli's Hydrodynamica, p. 279 ; in which the 

 repulsive force of a jet of water issuing from a hole in the 



* From the Philosophical Transactions for 1867, Part I., having been 

 read April 26, 1866. 



t Principia, 2nd Edition. 

 Phil. Mag. S. 4. Vol. 34. No. 228. August 1867. G 



