X 
Conten ts. 
Laboratory Note — Analysis of Titaniferous Iron Sand from North 
Berwick. By James Davidson, Esq. Communicated by Professor 
Crum Brown, ....... 523 
On some Permian Fishes, hitherto erroneously referred to the Genus 
Palceoniscus. By Dr Traquair, . , . . .525 
Note on the action of Bile Salts on the Animal Economy. By J. 
Graham Brown, Esq. Communicated by Dr M‘Kendrick, . . 525 
Preliminary Note on the Anatomy of the Pia Mater. By Dr J. Batty 
Tuke, . . . . . . . .534 
Note on the Physiological Action of Light. By James Dewar, Esq., 
and Dr M ‘Kendrick, ...... 534 
On the Expiatory and Substitutionary Sacrifices of the Greeks. By 
Dr Donaldson, ....... 535 
The Placenta in Ruminants — a Deciduate Placenta. By Professor 
Turner, . . . . . . . .537 
An Essay towards the General Solution of Numerical Equations of 
all Degrees. By W. H. Fox Talbot, Esq., Hon. F.R.S.E., . .514 
Note on the Electrical Conductivity of Saline Solutions. By J. G. 
Macgregor, M.A., B.Sc. Communicated by Professor Tait, . 545 
On High Flood Marks on the Banks of the River Tweed and some of 
its tributaries, and on Drift Deposits in Tweed Valley. By David 
Milne Home, LL.D., ...... 559 
Observations on Mr Sang’s Remarks relative to the Great Logarithmic 
Table compiled at the Bureau du Cadastre under the direction of 
M, Prony. By M. F. Lefort. Communicated by Mr Sang, who 
has translated the pa, per from the French, .... 563 
Observations relatives aux remarques publiees par M. Edward Sang 
dans les “ Proceedings of the Royal Society of Edinburgh, Session 
1874-1875,” sur les grandes tables logarithmiques et trigono- 
metriques calculees au Bureau du Cadastre sous la direction de 
Prony; par F. Lefort, Inspecteur general des Ponts et Chaussees, 
Membre Correspondant de l’Academie des Sciences des Naples, . 564 
Observation relative to Mr Edward Sang’s “ Remarks on the Great 
Logarithmic and Trigonometrical Tables calculated in the Bureau 
du Cadastre under the direction of Prony,” published in the Pro- 
ceedings of the Royal Society of Edinburgh, Session 1874-1875, 
by M. F. Lefort, Inspecteur General des Ponts et Chaussees Corre- 
sponding Member of the Academy of Sciences of Naples, . .574 
Reply to M. Lefort’s Observations. By Edward Sang, . .581 
Note on Electric Resistance of Solutions. By William Durham, Esq., 
and P. R. Scott Lang, M.A., ..... 587 
On the Circumscribed, Inscribed, and Escribed Circles of a Spherical 
Triangle. By C. G. Colson, Esq. Communicated by Professor 
Tait, ........ 589 
On some Remarkable Changes, Additions, and Omissions of Letters 
in Certain Cognate European Words. By the Hon. Lord 
Neaves, ........ 596 
