CONTENTS. *^1^ 



Letter on Terrestrial Magnetism, addressed to the Secretary. By 

 Professor Hanstecn of Clirbtiania, . . • • ^°° 



Notice of the occurrence in Scotland of the Tttrao wcdius, shewing 

 that supposed species to be a Hybrid. By James Wilson, 



Esq., -.,• ^ 



On the Coloration of the Blood. By the late Daniel Elhs, Esq. 



Communicated by Dr Christison, • ■ • .395 



On the Growth of the Salmon. By Mr Andrew Young, Invershin, 



Sutherlandshire. Communicated by James Wilson, Esq., . 398 

 On the property of transmitting Light, possessed by Charcoal and 



Plumbago, in fine plates and particles. By John Davy, M.D., 401 

 Chemical Observations on the Flowers of the Camellia Japonica, 



Magnolia grandiflora, and Chrysanthemum Leucanthemum, and 



on three proximate principles which they contain. Part I. By 



Dr Hope ^ • ' a 



On the Law of Visible position in Single and Bmocular V ision, and 



on the representation of SoUd Figures by the union of dissimilar 



piano pictures on the Retina. By Sir David Brewster, K.H., 405 

 Papers on Glaciers. No. I. Account of a Geometrical Survey of 



the Mer de Glace of Chamouni. By Professor Forbes, . 406 



On the Anatomy of the Human Placenta. By John Goodsir, 



On the mode in which Sound is produced and diffused, and on the 

 Vibrations caused in the quaUty of Sound by substance and 

 form. By Sir George S. Mackenzie, Bart., . • .409 



Papers on Glaciers. No. IL Describing the Rate of Motion of the 

 Ice of the Mer de Glace deduced from observation. By Pro- 

 fessor Forbes, 

 On the Nature, Locality, and Optical Phenomena of Muscae voli- 



tantes. By Sir David Brewster, K.H., . • • ^H 



On the Structure of the Lj-mphatic Glands. By John Goodsir, 



Jisq., . • • • • -o ■ 



On the Determination of Heights by the Temperature of Boihng 



Water. By Professor Forbes, ... . . 412 



Papers on Glaciers. No. IIL On the Structure of Glaciers, and the 



cause of their motion. By Professor Forbes, . . • 414 



Observations on the Temperature and Hygrometric state of the 

 Island of Barbadoes. By R. Lawson, Esq., Assistant- Surgeon 

 of H M. 47th Regiment. Communicated by Henry Marshall, 



Esq., • • «6 



On the Growth and Migration of the Sea Trout (Salmo Trutta). 

 By Mr John Shaw, Drumlanrig. Communicated by James 



Wilson, Esq *16 



Experiments with Hydro and Thermo Electric Currents ; and an 

 Examination of Metals long exposed to Thermo- Electric Cur- 

 rents. By R. Adie, Esq. Communicated by Dr Traill, . 417 

 Cliemical Observations on the Flowers of the Camellia Japonica, 

 Magnolia grandiflora, and Chrysanthemum Leucanthemum, and 



