CONTENTS. 
VII 
Pags 
Mr. Cornelius Varley on Natural Occurrences that impair the Vision of 
good Telescopes. : . 
Navigation. 
Rev. Dr. Scoresby on the Loss of the ‘Tayleur,’ and the Changes in the 
Action of Compasses in Iron Ships . 
—— -- Inquiry into the Principles and Measures on which Safety 
in the Navigation of Iron Ships may be reasonably looked for . 
Mr. J. T. Towson on the Inefficiency of the Aids of Science at present in con¬ 
nexion with the Compasses of Iron Ships . 
General Physics. 
Mr. W. Fairbairn on the Density of various Bodies when subjected to enor¬ 
mous compressing Forces. 
M. L. Foucault, Nouvellcs Experiences sur lt» Mouvement de la Terre an 
Moyen du Gyroscope. . . . . 
Mr. W. Hopkins’s Account of some Experiments on the Effect of Pressure on 
the Temperature of Fusion of different Substances. 
Mr. W. J. Macouorn Kankine on Formula’ for the Maximum Pressure and 
Latent Heat of Vapours . 
Professor W. Thomson on Mechanical Antecedents of Motion, Heat, and 
Light .. 
Mr. William Petrie on the Motion of Fluids ; a remarkable variation in tin- 
great Elementary Law of the ratio between Pressure ami Velocity . 
Mr. J. J. Watkkston on a Method of Computing the Absolute Volume of the 
Ultimate Particles of Liquids . 
66 
66 
67 
68 
69 
63 
63 
CHEMISTRY. 
Professor Thomas Anderson on the Constitution of Meconine and Papave¬ 
rine, and their Relations to the other Constituents of Opium . 1,1 
on the Alkaloids produced during the Destruc¬ 
tive Distillation of Animal Substances. .. ^ 
Mr. George Robert Berry on Collodion Negatives. w 
Professor F. Crace Calvert on the Physiological Properties of Carbazntic 
Acid. 
66 
on the Action of Gallic and Tannic Acid* on 
Iron aud Alumina Mordants. . *'■' 
on the Action of Citric, Tartaric and Oxalic- 
Acids on Cotton and Flax Fibres under the influence of Dry Heat and 
Pressure of Steam . *'•’ 
Mr. Andrew Crosse on the apparently Mechanical Action accompanvii^- 
Electric Transfer. Ml 
Mr. J. A. Davies on the Decomposition of Magnesian Limestone at Bro«l»- 
worth . r,t ' 
Dr. Edwards on Collodion Photographs of the Moon’s Surface 
