— 
KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM. 
PROCEEDINGS OF THE MEETING 
of Saturday January 30, 1909. 
—————— ES CO 
(Translated from: Verslag van de gewone vergadering der Wis- en Natuurkundige 
Afdeeling van Zaterdag 30 Januari 1909, Dl. XVII). 
e-O inl EN I AES: 
N. L. Sénncen: “The splitting up of ureum in the absence of albumen”. (Communicated by 
Prof. 8. HOOGEWERFF), p. 518. 
L. S. Ornstein: “Statistical Theory of Capillarity’. (Communicated by Prof. H. A, Lorentz), 
p. 526. 
P. H. ScHourr: “On fourdimensional nets and their sections by spaces”, (4th part), p. 543. 
(With 3 plates). 
J. P. VAN DER STOK: “On the duration of showers at Batavia”, p. 555. 
JAN DE Vrims: “On curves of order four with two fleenodal points or with two biflecnodal- 
points”, p. 568. 
Jan DE Vries: “On curves which can be generated by projective involutions of rays”, p. 576. 
J. D. vaN DER Waats Jr.: “On the law of the partition of energy in electrical systems”. 
(Communicated by Prof. J. D. van per Waats), p. 580. 
F. A. F. C. Went: “Some remarks on Sciaphila nana Br”, p. 590. 
A. BRESTER Jz.: “The Solar Vortices of Hale”. (Communicated by Prof. W. H. Juus), p. 592, 
Pu. Konnstamm: “On the course of the isobars of binary mixtures”. (Communicated by Prof 
J. D. vAN DER WAALS), p. 599. 
Erratum, p. 614. 
Microbiology. — “The splitting up of ureum in the absence of 
albumen.” By Dr. N. L. SÖHNGEN. (Communicated by Prof. 
S. HoOGEWERFF). 
(Communicated in the meeting of October 31, 1908). 
§ 1. General considerations. Ureum as a source of energy. 
Ureum, secreted as a product of the katabolism in the higher 
organized animal world, leaves the body, dissolved in urine. 
As such this nitrogen-compound cannot be assimilated by the higher 
vegetable world, and hence it would be of no practical impor- 
tance for us, if there were no fungi, especially certain microbes 
everywhere in the ground, which changed it into assimilable compounds, 
55 
Proceedings Royal Acad. Amsterdam. Vol. XI. 
