AMERICAN INSTITUTE. 195 



soon a large portion of the family cooking will be effected by it, 

 at least in the summer season. [A bronze medal awarded 



Vergnes^ Electro Dynamic Machine. 

 Maurice Yergnes, 710 Broadway, New-York. 



This machine is destined to transmit power of electricity, with 

 the greatest possible effect, contrary to all the others which have 

 been made for the same purpose, the more the dimensions are 

 increased the less it requires proportional electricity. 



The machine represented by our engraving was exhibited in 

 February, 1854. A, A, is an electromagnet employed by the wire 

 to excite it, and forming the diameter of a compact wheel; it 

 revolves within the multiplying coil B, B, and C, C, forming only 

 two multiplicators, divided as they appear solely for the admis- 

 sion of the axle ; they are alternately excited, so as to produce a 

 rotary motion of the magnet A, A. The knobs E, E, E, E, receive 

 separately the electricity of the magnet and the electricity of the 

 multiplicators by two separate batteries. By alternately pressing 

 the knobs D, D, the wheel changes its rotation. 



Since 1854, this machine has been wonderfully improved, prin- 

 cipally in this point, that the two multiplicators are not perpen- 

 dicular to each other, but parallel, and that each of them revolve 

 on the same shaft three electro magnets, one inside and two out- 

 side, and that those two systems of electro magnets are perpen- 

 dicular to each other. 



Prof Vergnes, the inventor, is about to make other improve- 

 ments in his machine at the Crystal Palace, in which the electro 

 magnets have no less than eight feet in length, weighing two 

 thousand pounds. 



Chichester^s Roller Gin. 



Union Roller Cotton Gin Co., 6 Liberty street. New- York. 



The machine represented in the accompanying engravings, figs. 

 1 and 2, is the invention of Mr. L. S. Chichester, and was pat- 

 ented on February 3d, of the present year. It is a roller gin. 

 One roller is steel, the other is iron covered with firm vulcanised 

 India rubber. The surface of the latter gives exactly the desired 

 action on the fiber, but would be very ill suited to resist seeds. 



