rr.-ervt | 
PHILOSOPH CAL SOCIETY 
WASHINGTON. 
PROCEEDINGS 
OF THE 
ROYAL SOCIETY OF EDINBURGH. 
Yol. XXIII. 
SESSIONS 1899 - 1900 — - 1900 - 1 . 
CONTENTS. 
By Lord Kelvih, 
Chairman’s Opening Address, Session 1899-1900. 
P.R.S.E., . • . 
On Swan’s Prism Photometer, commonly called Lunimer and Brodhuh 
Photometer. By Professor C. G. Knott, D.Sc., 
On the Thermo-electric Properties of Solid and Liquid Mercury. B 
Dr W. Peddie and A. B. Shand, Esq., .... 
The -Torsional Constants of Iron and Steel. By Dr W. Peddie, . 
On the Claim recently made for Gauss to the Invention (not the Dip 
covery) of Quaternions. By Professor Tait, 
Professor Klein’s View of Quaternions ; a Criticism. By Professor C. 
Knott, . . 
The Examination of Sea- Water by an Optical Method. By J. 
Manley, Magdalen College- Laboratory, Oxford. Communicated 
Sir John Murray, K.C.B., ..... 
Further Investigations on the Life-History of the Salmon in Fresh Watju. 
By D. Noel Paton, M.D., F.B.C.P.Ed., and M. I. Newbigin, D.Sc. 
On the Rectal Gland of the Elasmobranchs. By J. Crawford, M.3. 
C.M. Communicated by Dr Noel Paton. (With a Plate), . i . 
A New Form of Myograph and its Uses. By S. C. Mahalanobis, B.Se., 
F.R.M.S., F.R.S.E., Assistant Lecturer on Physiology, Univerdty 
College, Cardiff, .... 
The Presence of Enzymes in Normal and Pathological Tissues. By John 
Souttar M ‘Kendrick, M.D., . . . . . I . 
On the Law of Elastic Fatigue. {Abstract.) By Dr YV. Peddie, . 
PAGE 
12 
15 
16 
17 
24 
35 
44 
55 
62 
68 
90 
