CONTENTS. ix 
TRANSACTIONS OF THE SECTIONS. 
Section AA—MATHEMATICAL AND PHYSICAL SCIENCE. 
THURSDAY, SEPTEMBER 4. 
Page 
Address by J. W. L. Guatser, Se.D., F.R.S., V.P.R.A.S., President of the 
IE sorter teh oy cWns veld fearasscevesdassaasipaennanvnscne seep saneoapencravevav~unt 719 
1. Report of the Committee on Electro-optics .........scscesscoeenserseeeeeeeeeees 127 
2. Notes on High Vacua, By J. SWINBURNE ...........cecceceerscssteeeencanennens 727 
8. On the Use of the Lantern in Class-room Work. By Professor ARncH. 
Barr, D.Se., and Professor W. STROUD, D.Sc..........:eesseeeceeeeeeeeeerees 727 
4, On Refraction and Dispersion in certain Metals. By H. E. J. G. pu Bors 
Ete Pr CLINGS fay, de siaashiguseinsebensesv/dudenesansisn castles poideniedhbedss Jutsingvse oi evs 728 
5. On an Illustration of Contact Electricity presented by the Multicellular 
Electrometer. By Sir Wrtt1am Tomson, D.C.L., LL.D., F.R.S....... 728 
6. On Defective Colour Vision. By Lord Raytered, Sec.R.S............02 ees 728 
7. On some new Vacuum Joints and Taps. By W. A. SHENSTONE. ......... 729 
8. On the General Theory of Ventilation, with some Applications. By 
MEM MRS ERAS WMIVUEAte fae cclccces veldtee aces eccediceciocwes omedecbece ecceeeteceacetebale 730 
9. Account of Experiments to determine the Variations in Size of Drops 
with the Interval between the Fall of each. By W. Binnie, B.A.......... 731 
FRIDAY, SEPTEMBER 5. 
1. Recent Determinations of the Absolute Resistance of Mercury. By R. T. 
EGA ZMIRROOK,« MOA, EARS Gesncnstessicdarsscssaccecsvstdecvecceegtsborssndomoseess 731 
2. Suggestions towards a Determination of the Ohm, By Professor J. 
SSHIEACUTE ONES, IVs A sutiscaues ye culsaiocte ecodalectecslctods sinwicisls ow un sren’cOiteldeaueeieaasiice 732 
8. On Alternate Currents in Parallel Conductors of Homogeneous or 
Heterogeneous Substance. By Sir Witt1am Tuomson, D.C.L., LL.D., 
ee nc tee eRe en spun cimeaans cesldyacleh ans aguceneedscatmagean ius asunis hc tns 732 
4, On Anti-Effective Copper in Parallel Conductors or in Coiled Conductors 
for Alternate Currents. By Sir Witr1am Tuomson, D.C.L., LL.D., 
re ry eee ecient erences gas sca dace once es sexcuesbancavandecahand see womens senss 736 
5. The Molecular Theory of Induced Magnetism (with exhibition of a 
Model). By Professor J. A. Ewing, F.R.S. .......cccscsccscscesccevescsesencs 740 
6. Some Experiments to determine Wave Velocity in certain Dielectrics. 
Pa NIN ME ROULON Wavcssteces cuncsetelmestcentcetgeteciisersecdas aceubeeedmanoe-ehy 741 
e 
SATURDAY, SEPTEMBER 6. 
DEPARTMENT I.—MATHEMATICS. 
1. On the Physical Character of Caustic Surfaces. By J. Larmor............ 742 
i nosbucking of Plates, © By G, Hu BR YANci isis. sathiewesqescesscedsaeadénts 742 
