Prof. Faraday on some Points of Magnetic Philosophy. 83 



into Poggendorff's Annalen*, and of which I have only a very 

 imperfect knowledge by translated abstracts. He objects, as I 

 understand, to what I may call the physical part of my view as 

 assigning no origin for the lines, and as not presenting the higher 

 principle conveyed by the idea of magnetic fluids or of electric 

 currents : he says it does not displace the old theories, or render 

 them superfluous ; but I think I am right in believing, that, as 

 far as the lines are taken to be representations of the power, he 

 accepts them as correct representations, even to the full extent 

 of the hypotheses, either of magnetic fluids or electric currents. 

 It was always my intention to avoid substituting anything in 

 place of these fluids or currents, that the mind might be delivered 

 from the bondage of preconceived notions ; but for those who 

 desire an idea to rest upon, there is the old principle of the 

 sethers. 



3303. The encouragement I derive from this appreciation by 

 mathematicians of the mode of figuring to one's self the magnetic 

 forces by lines, emboldens me to dwell a little more upon the 

 further point of the true but unknown natural magnetic action. 

 Indeed, what we really want, is not a variety of different methods 

 of representing the forces, but the one true physical signification 

 of that which is rendered apparent to us by the phsenomena, and 

 the laws governing them. Of the two assumptions most usually 

 entertained at present, magnetic fluids and electric currents, one 

 must be wrong, perhaps both are ; and I do not perceive that the 

 mathematician, even though he may think that each contains 

 a higher principle than any I have advanced, can tell the true 

 from the false, or say that either is true. Neither of these views 

 could have led the mind to the phsenomena of diamagnetism, 

 and I think not to the magnetic rotation of light ; and I sup- 

 pose that if the question of the possibility of diamagnetic phse- 

 nomena could have been asked beforehand, a mathematician, 

 guided by either hypothesis, must have denied that possibility. 

 The notion that I have introduced complicates the matter still 

 further, for it is inconsistent with either of the former views, so 

 long as they depend exclusively upon action at a distance without 

 intermediation ; and yet in the form of lines of force it represents 

 magnetic actions truly in all that is not hypothetical. So that 

 there are now three fundamental notions, and two of them at 

 least must be impossible, i. e. untrue. 



3304. It is evident, therefore, that our physical views are very 

 doubtful; and I think good would result from an endeavour to 

 shake ourselves loose from such preconceptions as are contained 

 in them, that we may contemplate for a time the force as much as 

 possible in its purity. At present we cannot think of polarity 

 * PofrffenilorfFs Anvalen, 1853, vol. xc. p. 41/5. 



G2 



