GENERAL OBSERVATIONS 63 



I. c d' 



Fig. 35. 

 I. Electric Bell with Dry Element. 



a, Under part, with box, for the dry element ; b, roller for winding- 

 up the conducting wires ; c, dry element, with screw-clamp for 

 attachment of the conducting-wires ; c , conducting-wire leading 

 to the screw-clamp, with contact-spring in c , Fig. 2, or to the 

 wall in Fig. 3 ; d, upper part, with bell ; d', conducting-wire to the 

 shoe d' in Figs. 2, and 3 ; e, strap for slinging the apparatus 

 around the body of the assistant or rider ; /, connecting-wire 

 between bell and dry element. 



II. Hoof Shod with Shoe provided with Toe-piece and Calkins; 



Wall of the Hoof covered with Tinfoil. 

 a, Heel angle, with b, the contact-screws ; c, screw-clamp, with con- 

 tact-spring (isolated from the shoe) ; c conducting-wire from the 

 same; d, screw-clamp, with conducting-wire (d') screwed into 

 edge of the shoe; e, nails, isolated by cutting a small window 

 in the tinfoil. 



III. Hoof Shod with Plain Shoe; Horny Wall covered with 



Tinfoil. 



a, Toe and heel angle, with b, the contact-screws ; c, conducting-wire 

 passing from the tinfoil on the wall; d, conducting-wire passing 

 from the shoe ; c , d' ' , ends of the conducting-wires, which must 

 be imagined connected with the ends c , d' ', passing from the 

 apparatus. 



unconsciously, two separate observers were simultaneously 

 arriving by almost identical means at an equally satis- 

 factory answer to the question. Prior to the publication of 



