KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM, 
PROCEEDINGS OF THE MEETING 
of Saturday January 25, 1902. 
TOE OT 
(Translated from: Verslag van de gewone vergadering der Wis- en Natuurkundige 
Afdeeling van Zaterdag 25 Januari 1902, Dl. X). 
Contents: “The effect of the induction coil in telephonic apparatus” (I). By J. W. Girrav,. 
(Communicated by Prof. P. Zeeman), p. 357, (with 2 plates). — “Saline solutions 
with two boiling points and phenomena connected therewith”. By Prof. H. W. 
Baxkuuis RoozEBoom, p. 371. — “The Enantiotropy of Tin” (VII). By Prof. Ernst 
Conen. (Communicated by Prof. H. W. Baxuurs RoozeBoom), p. 377, (with 1 plate).— 
“The unfavourable condition of which complain the oyster cultivators on the Eastern- 
Schelde”. By Dr. P. P. C. Hoek, p. 379. — “A new law concerning the relation 
of stimulus and effect” (II). By Prof. J. K. A. WeRrTHEIM SALOMONSON. (Communi- 
cated by Prof. C. Wink er), p. 381. — “On the supply of sodium and chlorine by 
the rivers to the sea”. By Prof. Eve. Doegois. (Communicated by Prof. H. W. 
Bakuuis RoozeBooMm), p. 388. — ,,The effect of the induction coil in telephonic 
apparatus” (II). By J. W. Girray. (Communicated by Prof. P. ZEEMAN), p. 400, 
(with 1 plate). — “On Pepsin”. By Prof. C. A. PEKELHARING, p. 412. — “The 
differential equation of Moncr”. By Prof. W. KAPTEYN, p. 423. — “Factorisation of 
large numbers” (II). By F. J. Vars. (Communicated by Prof. P. H.Scnours), p. 425. 
The following papers were read: 
Physics. — “The effect of the induction coil in telephonic apparatus” 
(1st part). By J. W. Girray. (Communicated by Prof. P. 
ZEEMAN.) 
(Communicated in the meeting of November 30, 1901.) 
When HuvcuHes some twenty years ago announced his invention of the 
microphone, this simple apparatus at once drew the general attention. 
Everywhere experiments were made with it. The microphone was 
connected with a couple of Leclanché-cells and a telephone, and 
the sound of a ticking watch, etc. was transferred microphonically 
to the telephone. 
24 
Proceedings Royal Acad, Amsterdam. Vol. IV. 
