X 
CONTENTS. 
On the Structure of the Bark of Araucaria imbricata , with special 
reference to Palaeontology. By John Hutton Balfour, A.M., 
M.D., F.R.S., Sec. R.S.E., Professor of Medicine and Botany, . 577 
On the Theory of Numbers. By H. Fox Talbot, Esq., . . 582 
On the Carboniferous Volcanic Rocks of the Basin of the Forth. 
By Archibald Geikie, Esq., F.R.S., .... 582 
On the Constitution of Society in this Country, with reference to the 
Proportion which Male Life bears relatively to Female Life, and 
the Effects of an Excess of Female Life. Bj^ W. T. Thomson, 
Esq., . . . . ... . 583 
On the Danger of Hasty Generalisation in Geology. By Alexander 
Bryson, Esq., ...... 604 
On the Deflection of the Plummet caused by the Sun’s and Moon’s 
Attraction. By Edward Sang, .... 604 
Note on Gravity and Cohesion. By Professor William Thomson, 604 
Experimental Inquiry into the Laws of the Conduction of Heat in 
Bars, and into the Conducting Power of Wrought Iron. By 
Principal Forbes, . . . . . .607 
On certain Vegetable Formations in Calcareous Spar. By Princi- 
pal Sir David Brewster, . . . . .610 
On the Existence of Acari between the Laminae of Mica in Optical 
Contact. By Principal Sir David Brewster, . . . 610 
On the Secular Cooling of the Earth. By Professor William 
Thomson, ....... 610 
Notice of the Ravages of the Limnoria Terebrans on Creosoted 
Timber. By David Stevenson, Esq., F.R.S.E., M.I.C.E., &c., 612 
On some Thermic Properties of Water and Steam. By Professor 
W. J. Macquorn Rankine, . . . . .616 
Formulae connected with small continuous Displacements of the 
Particles of a Medium. By Professor Tait, . . .617 
