KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM, 
PROCEEDINGS OF THE MEETING 
of Saturday May 25, 1901. 
(Translated from: Verslag van de gewone vergadering der Wis- en Natuurkundige 
Afdeeling van Zaterdag 25 Mei 1901, Dl. X). 
Contents: On “Cadmiumamalgams’. By Prof. H, W. Bakxuuis RoozeBoom, p. 1. — “Further 
Researches concerning Oligonitrophilous Microbes”. By Prof. M. W. BEIJERINCK, p. 5. — 
“Further investigations on muscle-tone”. By Dr. J. W. LANGELAAN, (Communicated 
by Prof. T. Prace), p. 10. — “Special cases of Monae’s differential Equation”. By 
Prof. W. Kapreyn, p. 21. — “Precise Isothermals. 11. Accuracy of the measurement 
of pressure by means of the open manometer of KAMERLINGH ONNES”, p. 23. — 
II. “A waterbath of constant ordinary temperature” (with one plate), p. 29. — 
IV. “The calibration of Piezometertubes”, p. 35. By J. C. Scaatkwisk (Communi- 
cated by Prof. H. KAMERLINGH ONNES). — “On the repelling of ionisation of solutions 
of NaOH, Na, CO, and Na HCO, by addition of NaCl”. By Dr. A. Smits and L. K. 
Worrr. (Communicated by Prof. H. W. Baxuvis RoozreBoom), p. 42. — “Photo- 
bacteria as a reactive in the investigation of the chlorophyll-function”. By Prof. M. W. 
BEIJERINCK. p. 45. — “Plane waves of light in an homogeneous, electrically and magne- 
tically anisotropic dielectric”. By Frep. Scaun (Communicated by Prof. H. A. Lorentz), 
p. 49. — On “Bacteriologic Researches of Human Faeces”. (Ist Part). By Dr. Arex. 
Krein (Communicated by Prof. T. Prace), p. 65. —. “Synthesis of trioxybutyric acid 
(erythric acid)”. By C. Prey (Communicated by Prof. C. A. Lopry De BRUYN), p. 77. — 
“On a-hydroxybutenoic acid (vidylglycollic acid) and its decompositions’. By G. 
VAN DER SLEEN (Communicated by Prof. C. A, Lopry DE Bruyn), p. 79. 
The following papers were read: 
Chemistry. — Professor H. W. Baknuis ROOZEBOOM presents a 
communication on “Cadmiwm amalgams.” 
The desirability of the investigation of the nature of the cadmium 
amalgams arises from the use of these amalgams in the WEsrTon-cell. 
The discussion ') about the irregularities occurring when using this 
cell could not lead to a satisfactory conclusion until a better insight 
1) Compare Proceedings of June 30 and Oct. 27 1900 and Hebr. 23 1901. 
I 
Proceedings Royal Acad. Amsterdam. Vol. IV. 
