XIV CONTENTS. 



ROTATION (Observations on the niagnelie) of the phine of polarisation in the interior 

 of an aljborptionhand. 41. 



— (Measurements on the magnetic) of the phine of pohirisation in ii(|uetied gases 

 under atmosplieric pressure. 243. 



— (The cakuhition --- from the magnetic) (jf tlie phine of pohirisation lor suhstauces 



/// 



without an al)sorplionbaud in the visible spectrum. 413. 

 ROTATIONS (Five) in S/^ in ecjuililn-inm. 362. 



SAL o M ON SON (j. K. A. w E R Ï 11 F, I m). i^ee Werthkim .Salomonson (J. K. A.). 

 SAND K R A K H Ü Y z E N (E. 1'. V A N 1) E). Ou the yearly periodicity of' the rates 



of tlie standardclock of the 01)servatory at Leyden, llohwii 11°. 17. (I). 68. (If). llt-S. 



— Preliminary investigation of the rate of the standardclocic of the Observatory at 

 Leyden, llohwii 11°. 17 after it was mounted in the niche of the great pier. 207. 



SANUE HAKHUYZEN (h. g. VAN u E) presents a paper of Mr. J. Weeder: 



"On interpolation based on a supposed condition of minimum". 364. 

 s c II f) u T E (j. c ). Die Stclar-ïheorie. 497. 



sen U Ï E (P. H.). On the connection of the jilancs of position of the angles formed 

 by two spaces -S'a passing through a point and incident spacial systems. 53. 



— presents a paper of Dr. ^. L. vanOss: "Five rotations in ■S'j in equilibrium." 362. 



— Relations between diagonals of parallelotopes. 540. 



s c II R Ü E DER VAN DER KOLK (J. L. c.) presents a paper of Mr. A. 11. SiRKs: 

 '•On the advantage of metal-etching by means of the electric current." 219. 



presents a paper of Mr. E. 11. M. Heekman : "On the behaviour of distiiene and 



of sillimanite at high temperature". 240. 



presents a paper of Mr. P. Tesch: "On the refractive index of rock-glasses''. 602. 



presents a paper of .Vlr. G. H. Hogenra.vd: "On an ,/Eisenrose" of the St. 



Gotthard." 605. 

 SHADING (On maxima and minima of intensity sometimes observed within the) of 



strongly widened spectral lines. 662. 

 siEKTSEMA (L. H.). Measurements on the magnetic rotation ol' the plane of pola- 

 risation in liquefied gases under atmospheric pressure. 11. Measurements with 

 Methylchloride. 243. 



The calculation ~ from the magnetic rotation of the plane of polarisation for 



III 



substances without an absorptionband in tlie visible sjiectrum. 413. 

 SILICEOUS SPICULES (On the shape of some) of sponges. 104. 

 SILLIMANITE (On the behaviour of distheue and of) at high tem])erature. 250. 

 siRKS (A. u.). On the advantage ot metal-etching by means of the electric current. 21 y. 



Some remarkable phenomena, concerning the electric circuit in electrolytes. 465. 



SMITS (a.) and L. K. Wolff. The velocity of transformation of carbon monoxide. 417. 

 SOLAR prominences (An hypothesis on the nature of). 162. 

 solution (Dissociation in and crystallisation from a solid). (543. 



SPACE (A representation in) of the regions in which the solid phases which occur, 

 are the components, when not forming compounds. 27^. 



