VIII GON "ETSEN Las. 
KAMERLINGH ONNES (H.) and C. BRAAK. On the measurement of very low tem- 
peratures. XXI. On the standardizing of temperatures by means of boiling points of 
pure substances. The determination of the vapour pressure of oxygen at three 
temperatures. 333. 
KAMERLINGH ONNES (u.). and J. Cray. On the measurement of very low 
temperatures, XXII. The thermo element gold-silver at liquid hydrogen tempe- 
ratures. 344. 
— On the change of the resistance of pure metals at very low temperatures and 
the influence exerted on it by small amounts of admixtures. IL, 345. 
KAPTEYN (w.). On a theorem of PaINLEVE. 459. 
— On a class of differential equations of the first order and the first degree. 813. 
KARSTEN (Miss-B. 3) and E.H. Bicuner. On the system: hydrogen bromide 
and bromine, 494. 
KEESING (A). On plaitpoint temperatures of the system water-phenol. 394. 
KINETIC DERIVATION (On the) of the second law of thermodynamics, 303. - 
KLUYVER (J. c.). An integral-theorem of GEGENBAUER. 749. 
KOHNSTAMM (ei) On the course of the isobars of binary systems. 599. IL. 799, 
III. 906. 
KOHNSTAMM (PH.) and J. Cur. Reepers. On the phenomena of condensation for 
mixtures of carbonic acid and urethane, in connection with double retrograde 
condensation. 913. 
KOORDERs (S. H). Contribution N°. 1 to the knowledge of the flora of Java. 3rd 
Continuation, 129. 4th Continuation. 158. 
— Some systematic and phytogeograpiical notes on the Javanese Casuarinaceae, 
especially of the State Herbaria at Leiden and at Utrecht. 415. 
— Polyporandra Junghuhnii, a hitherto undescribed species of the order of Leacina- 
ceae, found in ’s Rijks Herbarium at Leiden. 763. 
KORTEWEG (D J.) presents a paper of Dr. L. E. J. Brouwer: “About difference 
quotients and differentialquotients.” 59, 
— presents a paper of Dr. J. A. Barrau: “On triple systems, particularly those of 
thirteen elements.” 290. 
— presents a paper of Dr. J. A. Barrau: “On the combinatory problem of 
STEINER.” 352. 
— presents a paper of Dr. L. E. J. Brouwer: “Continuous one-one transforma- 
tions of surfaces in themselves.” 788. 
— presents a paper of Dr. L. E. J. Brouwer: “On continuous vector distributions 
on surfaces.” 850. 
LAAR (J. J. VAN). On the solid state. 765. 
LATENT IMAGE (A contribution to our knowledge of the solarization phenomenon and 
of some other properties of the). 2. 
LAW of molecular attraction (On the) for electrical double points. 132. 315. 
— of thermodynamics (On the kinetic derivation of the second). 503. 
— of the partition of energy (On the) in electrical systems. 580. 
— of shift (The) of the central component of a triplet in a magnetic field. 473, 
LAYERS (The age of the) of Sondé and Trinil on Java, 185, 
LEAVES (Carbon dioxide transport in). 649, 
