116 PROCEEDINGS OF THE REGENTS. 



necessary to success explained in that paper; that instead of the 

 battery of a single element, he should employ one of a number of 

 pairs ; and that, in place of the magnet with a short single wire, he 

 should use one with a long coil. Dr. Gale further stated that his 

 apparatus was in the same building, and that having articles of- the 

 kind he had mentioned, he procured them, and that with these the 

 action was produced through a circuit of half a mile of wire.* To this 

 statement Mr. Morse made no reply. The interview then terminated, 

 and I have since had no further communication with him on the subject. 



5. Please state whether or not you ever constructed any machine 

 for producing motion by magnetic attraction and repulsion ; if yea, 

 what was it, and what led to the making of it. 



Answer. — After developing the great magnetic power of the electro- 

 magnet as already described, the thought occurred to me that this 

 power might be applied to give motion to a machine. The simplest 

 arrangement which suggested itself to my mind was one already re- 

 ferred to, namely, causing a movable bar, supported on a horizontal 

 axis like a scale beam, to be attracted and repelled by two permanent 

 magnets. This could be readily effected by transmitting through a 

 coil of wire around the suspended bar a current of galvanism, first in 

 one direction, and then in the opposite direction, the alternations of 

 the current being produced by dipping the ends of wires projecting 

 from the coils into cups of mercury connected with batteries, one on 

 either side. An account of tliis was published in Silliman's Journal, 

 for 1831, vol. XX., p. 340. It was the first successful attempt to pro- 

 duce a mechanical motion which might apparently be employed in 

 the arts as a motive power. This little machine attracted much atten- 

 tion at home and abroad, and various modifications of it were made 

 by myself and others. I never, however, regarded it as practically 

 applicable in the arts, because of the great expense of producing 

 power by this means, except, perhaps, in particular cases where ex- 

 pense of power is of little consequence. 



6. Please look at the drawings of the Columbian telegraph, now 

 shown you, marked G. W. B. and N. B. C, and certified by G. S. Hil- 

 lard, Commissioner. Describe generally the apparatus represeated 

 and its mode of operation, and state in what respects, if any, it differs 

 from the telegraphic apparatus patented by Mr. Morse. 



Answer. — I have looked at the drawings, and I find, on examina- 

 tion, that it will be impossible for me to give a definite answer to the 

 question, unless I have more time than is now at my disposal, and 

 the means of examining and comparing the operations of the 

 machines. 



7. Please state, if you can, how many original experiments you 

 have made in the course of your investigations in electricity, mag- 

 netism, and electro-magnetism. 



Answer. — The experiments I have mentioned in this deposition 

 form but a small part of my original investigations. Besides many 



* See Dr. ale's letter of April 7, 1856, page 93. 



