812 
Proceedings of Royal Society of Edinburgh . [sess. 
2. On a Relation between Two Groups of Four Vectors. By Professor 
Tait. P. xvi. 89. 
3. Description of a Portable Apparatus for Counting tbe Dust 
Particles in the Atmosphere. By John Aitken, Esq., F.R.S. P. xvi. 
169. 
4. On the Stomach of the Narwhal ( Monodon monoceros). By G. 
Sims Woodhead, M.D., and R. W. Gray, Esq. P. xvi. 792. 
5. Researches on Micro-Organisms, &c. Part. III. By Dr A. B. 
Griffiths, F.C.S. 
6. By permission of the Meeting, there were laid on the table 
Additional Remarks on the Virial of Molecular Force, by Professor Tait. 
Monday, 1st April 1889. 
Sir William Thomson, President, in the Chair. 
The following Communications were read : — 
1. On the Duration of Impact. By Professor Tait. 
2. On New Forms of Magneto-Static Current- and Volt-meters, and 
on an Electro-Static Voltmeter, with Multiple Voltaic Pile facilitating 
Graduation. By Sir W. Thomson. ( The Instruments were exhibited.) 
3. On the Properties of Manganese Steel. By A. Crichton 
Mitchell, Esq. T. xxxv. 
4. On an Improved Method of Measuring small Rotations of the 
Plane of Polarization by ordinary Apparatus. By W. Peddie, D.Sc. 
5. On the Relations among the Line-, Surface-, and Volume- Integrals. 
By Professor Tait. P. xvi. 257. 
The following Candidates for Fellowship were balloted for, and 
declared duly elected Fellows of the Society: — 
John Alison, Esq., M.A. 
R. W. Philip, M.D., M.A., F.R.C.P.E. 
T. Edgar Underhill, M.D., F.R.C.S.E. 
Monday , 1 5th April 1889. 
Sir Douglas Maclagan, M.D., Vice-President, in the Chair. 
PRIZES. 
The Chairman presented the Keith Prize, for 1885-87, to Mr 
J. Y. Buchanan, for a valuable Series of Communications, extending 
over several years, on subjects connected with Ocean Circulation, 
Compressibility of Glass, &c., two of which, viz., “On Ice and 
Brines,” and “On the Distribution of Temperature in the Antarctic 
