In connection with this it is interesting to note how, all unconsciously,
two separate observers were simultaneously arriving by almost identical
means at an equally satisfactory answer to the question. Prior to the
publication of Lungwitz's article on the subject, Colonel F. Smith, A.V.D.,
had arrived at similar conclusions by working on the same methods.

[Illustration: Fig. 35. I. Electric Bell with Dry Element. a, Under
part, with box, for the dry element; 6, 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; f,
connecting-wire between bell and dry element.]

[Illustration: Fig. 35. 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 contact-spring (isolated from
the shoe); c' conducting-wire from the same; d, screw-clamp, with
conducting-wire (d') screwed into the edge of the shoe; e, nails isolated
by cutting a small window in the tinfoil.]

[Illustration: Fig. 35. 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.]

It is unnecessary for our purpose here to minutely describe the exact
_modus operandi_ of these two experimenters. Briefly, the method of inquiry