KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM, 
PROCEEDINGS OF THE MEETING 
of Saturday September 30th, 1899, 
ir : 
(Translated from: Verslag van de gewone vergadering der Wis- en Natuurkundige 
Afdeeling van Zaterdag 30 September 1899 DI. VIII), 
Contents: “On the influence of water on the velocity of the formation of ether”. By Prof. 
C. A. Lopry pe Bruyn and Dr. A. Srecer, p. 71. — “An example of the conversion 
of mixed crystals into a compound”. By Prof. H. W. Baxuurs RoozesBoom, p. 74. — 
“On the Enantiotropy of Tin”. By Dr. Ernst COHEN and Dr. C. van Eyk (Communi- 
cated by Prof. H. W. Baxnurs RoozrBoom), p. 77. — “On the Enantiotropy of Tin 
II)”. By Dr. Ernst COHEN and Dr. C. van Eyk (Communicated by Prof. H. W. 
Bakuvuis Roozrsoom), p. 81. — “The mixture crystals of Hg J, with Hg Br,”. By 
Prof. H. W. Baknvis RoozeBoom, p. 81. — “On a new kind of Transition Elements 
(sixth kind)”. By Dr. Ernst Conen (Communicated by Prof. H. W. Bakuuis Rooze- 
Boom), p. 81, — “On Isodialdane”. By Prof. C. A. Lopry pe Bruyn and Mr. H.C. Byt, 
p. 81. — “The results of a comparative investigation concerning the palatine-, orbital- 
and temporal regions of the Monotreme-skull”. By Dr. J. F. van BEMMELEN (Commu- 
nicated by Prof, A. A. W. Husrecur), p.81. — “On the Formation of the Resultant”. 
By Mr. K. Bes (Communicated by Prof. J. CARDINAAL), p. 85. — “Investigations 
with the Mieromanometer”. By Dr. A. Smirs (Communicated by Prof. V. A. JuLius), 
p. 88. — “The determination of the refractivity as a method for the investigation of 
the composition of co-existing phases in mixtures of acetone and ether”. By Mr. 
E. H. J. Cunaeus (Communicated by Prof. J. D. van per Waars) with one plate, 
p- 101. — “On the Theory of Lippmann’s Capillary Electrometer”. By Prof. W. Erxr- 
HOVEN (Communicated by Prof. T. ZAAYER), p. 108, — “On the formation of Indigo 
from the Woad (Isatis tinctoria)”. By Prof. M. W. Beiserinck, p. 120. — “Methods 
and Apparatus used in the Cryogenic Laboratory (1)”. By Prof. H. KAMERLINGH 
Onnes (with 4 plates), p. 129. — “The dielectric constants of liquid nitrous oxide 
and oxygen”. By Dr. Frirz Hasenornre (Communicated by Prof. H. KAMERLINGIL 
ONNES), p. 140. — “On Spasms in the Earth’s magnetie force”. By Dr. W. van Bem- 
MELEN (Communicated by Prof. H. KAMERLINGH ONNES), p. 141. — Erratum, 141. 
The following papers were read: 
Chemistry. — „On the influence of water on the velocity of the 
formation of ether.” By Prof. C. A. LoBry pe Bruyn and 
Dr. A. STEGER. 
(Read in the meeting of June 24th 1899), 
In a previous communication ') we drew attention to the influence 
of water on the velocity with which oxyethyl or oxymethyl is sub- 
!) Proceedings 1898 p. 166. 
6 
Proceedings Royal Acad, Amsterdam, Vol. LL, 
