IV 
Contents. 
PAGE 
Uses of Metallic Nickel and Oxides of Cobalt. By J. B. Read- 
man, Esq., . . . . . . . .65 
Note on a Singular Passage in the Principia. By Professor 
Tait, ......... 72 
The Graphic Analysis of the Kinematics of Rigid- Bar Mechanisms. 
By Professor R. Smith. Communicated by Professor Tait, . 78 
Note on the Necessity for a Condensation-Nucleus. By Professor 
Tait, . . . . . . . . .78 
President’s Address, . . . . . . .80 
On Evaporation and Condensation. By Professor Tait, . .91 
Note on Ectocarpus. By John Rattray, B.Sc. Communicated by 
John Murray, Esq., . . . . . .94 
Some Remarkable Concretions, collected in the neighbourhood of 
Philadelphia by the Rev. J. M. Macdonald, . . .94 
Preliminary Report on the Cephalopoda collected during the Cruise 
of H.M.S. “Challenger.” Part I. The Octopoda. By William 
E. Hoyle, M.A. (Oxon.), M.R.C.S., . . . . .94 
On Energy in Vortex Motion. By Sir William Thomson, . . 114 
The Theory of Determinants in the Historical Order of its Develop- 
ment. Part I. Determinants in General (1693-1800). By Dr 
Thomas Muir, . . . . . . .114 
On Bipartite Functions. By Dr Thomas Muir, . . .114 
Note on Galois’ Theorem regarding the continued Fraction Represen- 
tations of the Roots of an Equation. By Dr Thomas Muir, . 114 
Letter from Professor Michie Smith on the Zodiacal Light, and on 
the Origin of Atmospheric Electricity, . . . .114 
On a New Form of Chromotrope. By John Aitken, Esq., . .116 
On the Application of the Atometer. By Professor Tait, . .116 
An Address on the Recent Progress of the Geological Survey of the 
United Kingdom, . . . . . . .117 
Hooke’s Anticipation of the Kinetic Theory and of Synchronism. 
By Professor Tait, . . . . . . .118 
On the Hexagonal System in Crystallography. By Professor Crum 
Brown, ........ 118 
On the Effect of Temperature on the Compressibility of Water. By 
Professor Tait, . . . . . . .120 
Chemico-Physiological Investigations on the Cephalopod Liver, and 
its identity as a true Pancreas. By Dr A. B. Griffiths, Ph.D., 
F. C.S. (Lond. and Paris), Lecturer on Chemistry and Physics, 
Technical College, Manchester, &c. Communicated by W. E. 
Hoyle, Esq., M.A., ....... 120 
Chromomictors. By John Aitken, . . . . .122 
On Chlorophyll from the Deep Sea. By W. W. Hartley, F.R.S., 
Royal College of Science, Dublin, . . .130 
