436 Michael Faraday, his Life and Works. 



fore his works, I have no doubt, will always be regarded as 

 corner- stones in the new edifice which we are now endeavouring 

 to construct. 



I designedly say, which we are endeavouring to construct; for 

 we must carefully avoid thinking that it is already constructed. 

 Since the fine discovery of the mechanical equivalent of heat, it 

 seems as if everything had been said and everything were easily 

 explained by means simply of a ponderable matter, an imponde- 

 rable sether, and a mechanical impulse. Vulgarizers of science, 

 more anxious to produce an effect than to remain faithful to sci- 

 entific truth, proclaim a molecular system of the world destined 

 to form a pendant to the Mecanique Celeste of Laplace. Accord- 

 ing to them, nothing is more simple, nothing clearer ; attraction 

 itself, which has been the object of the study of so many superior 

 minds, is merely the effect of an impulse easy to understand. A 

 dangerous illusion ! which, if it succeeded in propagating itself, 

 would be as fatal to the true progress of science as opposed to 

 its useful diffusion ; for it is especially upon those who take to 

 themselves the high mission of popularizing science that it is 

 imperiously incumbent to spread none but correct and well- 

 founded ideas. 



Let us not, however, exaggerate anything, or refuse to recog- 

 nize in the too positive ideas which we have just combated that 

 portion of truth which they may contain. With this purpose let 

 us try, in conclusion, to lay down in few w r ords the point at 

 which, in our opinion, in the present state of science the import- 

 ant question of the unity of forces has arrived. 



After having for a long time arrested the progress of science 

 by abstract and general considerations upon the phenomena of 

 nature, the philosophers finished by adopting, with Galileo, the 

 experimental method, the only one that can lead with certainty 

 to the discovery of the truth. A rigorous and profound analysis, 

 placed at the service of this method, furnished certain and 

 fundamental results. Reverting to a synthetic phase, many 

 superior minds now seek by means of these tediously and painfully 

 collected materials to reconstruct the edifice of which the raising- 

 was formerly attempted in vain. No doubt science has thus en- 

 tered upon a fertile course, but only on condition of advancing 

 with sure and consequently with slow steps. We speak of the 

 unity of force, and of the transformation of forces one into 

 the other ; but do we know what are forces ? do we know 

 their nature? We have certainly proved transformations of 

 movement, and shown that one work may change into another 

 work, mechanical motion into heat, and heat into mechanical 

 motion ; these are, without doubt, the most important points 

 gained by science, and enable us to get a glimpse of the existence 



