CONTENTS. 
Opening Address, Session 1857-58. By Dr Christison, Page 2 
Excursions in the Troad, with Observations on its Topography and 
Antiquities. Part I. By Dr William Robertson, F.R.C.P. 
Communicated by Dr J. Y. Simpson, . . . .17 
Biographical Notices of MM. Thenard and Cauchy, two recently 
deceased Foreign Members of the Society. By Professor Kelland, 30 
Excursions in the Troad, with Observations on its Topography and 
Antiquities. By Dr William Robertson, F.R.C.P. Communi- 
cated by Dr J. Y. Simpson, . . . . .41 
On the Composition of the Building Sandstones of Craigleith, Binnie, 
Gifnock, and Partick Bridge. By Mr Thomas Bloxam, Assistant 
Chemist Laboratory of Industrial Museum. With a Preli- 
minary Note by Professor G. Wilson, Director of the Industrial 
Museum, . . . . . . .42 
On the Structure of the Reproductive Organs in some of the Hy- 
droid Polypes. By Dr Allman, , . . .50 
On the Focal Adaptation of the Eye in Man and some Animals. By 
Dr James Black, F.G.S. Illustrated by enlarged Diagrams, . 64 
Note on the Black Lustrous Yarnish of Ancient Pottery. By 
John Davy, M.D., F.R.SS. Lond. and Edin., . . .65 
On the Mechanism of the Knee-Joint. By Professor Goodsir, 67 
On the Form and Origin of the Symbols on the Ancient Sculptured 
Stones of Scotland. By Dr Wise, . . . .73 
Notes on the Structure of Amphora, a Genus of Diatomaceae, and 
the Diagnosis of its Species. By Dr Walker Arnott, . .74 
Description of the Sulphur Mine near Conil ; preceded by a Notice 
of the Geological Features of the Southern portion of Andalusia. 
By Dr Traill, . . . . . .78 
Remarks on a Slab of Sandstone, containing numerous Cavities, ap- 
parently produced by Marine Animals. By Charles Maclaren, 
Esq., . . . . . . .80 
Notice respecting some Artificial Sections, illustrating the Geology 
of Chamouni. By John Ruskin, Esq. Communicated by Pro- 
fessor Forbes, . . . . . .82 
Professor Kelland’s Address on delivering the Keith Medal to Pro- 
fessor Boole of Cork, . . . . . .84 
On the Average Value of Human Testimony. By Bishop Terrot, 87 
On the Tides in the Sound of Harris. By Henry C. Otter, Esq., 
R.N., Captain H.M.S. “ Porcupine.” Communicated by Dr 
Stark, . . . . . . .89 
