XI CONTENTS 
JAEGER (FP. M.) and H. Haca. On the symmetry of the Röntgen-patterns of 
trigonal and hexagonal erystals, and on normal and abnormal diffraction-images 
of birefringent crystals in general. 542. 
— On the symmetry of the Röntgen-patterns of rhombic crystals. L. 559. 
— The symmetry of the Röntgen-patterns of monoclinic crystals. 1201. 
— The symmetry of the Röntgen-patterns of tetragonal crystals. 1350. 
— On Röntgen-patterns of isomorphous crystals. 1357. 
— On the symmetry of the Röntgen-patterns of triclinie and some rhombic 
erystals, and some remarks on the diffraction-images of quartz. 1552. 
— and Jur. Kaun. Investigations on the temperature-coefficients of the free molecular 
surface -energy of liquids at temperatures from —S80° to 1650° C. LX. 75. X 269. 
Xt, 285. XII. 297. XILI. 595. XIV. 617. 
— and van KLooster. Investigations in the field of silicate-chemistry. LV. Some 
data on the meta- and ortho-silicates of the bivalent metals : Beryllium, Magnesium, 
Calcium, Strontium, Barium, Zinc, Cadmium and Manganese, 896. 
Java (Contribution to the flora of). VIII. 521. 
JONG (A. W. K. DE). Action of sunlight on the cinnamie acids 181. 751. 
JONG (C. DE) and E‚ F. van pg SANDE BAKHUYZEN. On the influence exercised by 
the systematic connection between the parallax of the stars and their apparent 
distance from the galactic plane upon the determination of the precessional 
constant and of the systematic proper motions of the stars. 683. 
JULIUS {W. H.). A test of the dispersion theory of solar phenomena, derived from 
measurements by Apams and St. Jorn on the displacements of FRAUNHOPER lines 
in the spectra of the sun’s limb and of sun-spots. 1691. 
— Anomalous dispersion and FrauNuorer lines. Reply to objections. 1691. 
JUPITER’S SATELLITES (On the orbital planes of) as derived from measurements made 
at Berlin. 1012. 
KAHN (JUL) and V. M. Jarcer. Investigations ou the temperature-coefficients of 
the free molecular surface-energy of liquids at temperatures from — 80° to 1650° C. 
IX. 75. X. 269. XI, 285. XIL 297. XIIL 595. XLV. 617. 
KALOEE (Lamiang district S. E. Atjeh) (On a trilobite fauna of presumably devonian age 
in the Dutch East Indies near). 1632. 
KAMERLINGH ONNEs (H.) v. Onnes (H. KaMERLINGH). 
KAPTEYN (W.) presents a paper of Prof. J. G. Ruraers: “On a linear integral 
equation of VorrerrA of the first kind, whose kernel contains a function of 
BEssEL”’. 769. 
KEESOM (w. H.). The second virial coefficient for rigid spherical molecules, whose 
mutual attraction is equivalent to that of a quadruplet placed at their centre. 636. 
— ‘Iwo theorems concerning the second virial coefficient for rigid spherical molecules 
which besides collisional forces only exert CouLoms-forces and for which the 
total charge of the active agent is zero. 868. 
— and H. KaMeRLINGH ONNEs. The specific heat at low temperatures. II. 484. II]. 1247. 
— and Miss C. van Leeuwen. On the second virial coefficient for rigid spherical 
molecules carrying quadruplets. 1568. 
