558 Professor Faraday, on Wheatstone's [June 11, 



In the first instruments powerful magnets were used, and 

 keepers with heavy coils associated with them. When magnetic 

 electricity was first discovered, the signs were feeble, and the mind 

 of the student was led to increase the results by increasing the force 

 and size of the instruments. When the object was to obtain a 

 current sufficient to give signals through long circuits, large appa- 

 ratus were employed, but these involved the inconveniences of 

 inertia and momentum ; the keeper was not set in motion at once, 

 nor instantly stopped ; and, if connected directly with the reading 

 indexes, these circumstances caused an occasional uncertainty of 

 action. Prepared by its previous education, the mind could per- 

 ceive the disadvantages of these influences, and could proceed to 

 their removal ; and now a small magnet is used to send sufficient 

 currents through 12, 20, 50, a hundred, or several hundred miles; 

 a keeper and helix is associated with it, which the hand can easily 

 put in motion ; and the currents are not sent out of the indicating 

 instrument to tell their story, until a key is depressed, and thus 

 irregularity contingent upon first action is removed. A small 

 magnet, ever ready for action and never wasting, can replace the 

 voltaic battery ; if powerful agencies be required, the electro- 

 magnet can be employed without any change in principle or 

 telegraphic practice ; and as magneto-electric currents have special 

 advantages over voltaic currents, these are in every case retained. 

 These advantages I consider as the results of scientific education, 

 much of it not tutorial, but of self : but there is a special privilege 

 about the science-branch of education, namely, that what is personal 

 in the first instance immediately becomes an addition to the stock 

 of scientific learning, and passes into the hands of the tutor, to be 

 used by him in the education of others, and enable them in turn 

 to educate themselves. How well may the young man entering 

 upon his studies in electricity be taught by what is past to 

 watch for the smallest signs of action, new or old ; to nurse them 

 up by any means until they have gained strength ; then to study 

 their laws, to eliminate the essential conditions from the non- 

 essential, and at last, to refine again, until the encumbering matter 

 is as much as possible dismissed, and the power left in its highly 

 developed and most exalted state. 



The alternations or successions of currents produced by the 

 movement of the keeper at the communicator, pass along the wire to 

 the indicator at a distance ; there each one for itself confers a 

 magnetic condition on a piece of soft iron, and renders it attractive 

 or repulsive of small permanent magnets ; and these acting in turn 

 on a propelment, cause the index to pass at will from one letter to 

 another on the dial face. The first electro-magnets, i.e. those made 

 by the circulation of an electric current round a piece of soft iron, 

 were weak ; they were quickly strengthened, and it was only when 

 they were strong, that their laws and actions could be successfully 

 investigated. But now they were required small, yet potential. 



