in detail from those instituted by Mr. Ader at the exhibition of 1881;
and Mr. Hospitalier presented a new form of an experiment devised by
Mr. Giltay, consisting of a telephonic transmission of sounds without
the use of receivers. Mr. Giltay's experiment is nothing but Mr.
Dunand's speaking condenser without the condenser. A glance at Fig. 1
will show how things are arranged for the experiment. The transmitting
system comprises two distinct circuits, viz.: (1) one formed of a
pile, P, of 2 or 3 Leclanche elements, or of 1 or 2 small sized
accumulators, an Ader microphane transmitter, M, and the inducting
wire of a small induction coil, B; and (2) the other formed of the
induced wire of the coil, B, of a pile, P', of 10 or 12 Leclanche
elements, and of a line whose extremities terminate at R, in two
ordinary electro-medical handles. With this arrangement the experiment
performed is as follows: When any one speaks or sings in front of the
transmitter, T, while two persons, A and B, each having one hand
gloved, are holding the handles in the ungloved hand, it is only
necessary for A to place his gloved hand upon B's ear, or for the
latter to place his hand upon A's, or for each to place his hand on
the other's ear simultaneously, in order that A or B, or A and B
simultaneously, may hear a voice issuing from the glove. Under these
circumstances, Mr. Giltay's experiment is explained like Dunand's
speaking condenser--the hand of A and the ear of B here constituting
the armature of an elementary condenser in which the glove performs
the role of dielectric.

Upon repeating this experiment at the laboratory of the School of
Physics and Industrial Chemistry of Paris, it has been found that the
glove maybe replaced by a sheet of plain or paraffined paper. In this
case, when two persons are holding the handles, and have their ears
applied, one against the other, if a sheet of paper be interposed,
airs or words will be heard to proceed therefrom. Finally, it has been
found possible to entirely suppress the paper, or dielectric, and to
hear directly, by simply interposing the auditor or auditors in the
circuit. One of the most curious forms of the experiment is the one
shown in Fig. 2. Here a third person, C, hears the hands of A and B
speak when a circuit is formed by means of three persons, A, B, and C,
the two former, A and B, each holding one of the wires of the circuit
and applying his free hand to the ear of C. Although the