419 



tinum, cadmium, silver, and iron, was increased, by passing them 

 through the drawing- plate, a deflection of from one to four degrees 

 was occasioned in the galvanometer ; but with lead and tin no per- 

 ceptible deflection was occasioned. 



The following Donations of Books to the Society's Library 

 were announced. 



Bulletin dcs Seances de la Societe Vaudoise des Sciences NaturcUes. 



Nos. 1 & 4. — By the Society. 

 Essai Historique sur Ics Phenomenes et les Doctrines de I'Electro- 



Chimie. Par Elie Francois Wartniann. — By the Author. 

 Comptes Rendus Hebdoniadaii'es des Seances de 1' Academic des 



Sciences. Tome XVI. Nos. 8 & 9. — By the Society. 

 On the Transparency of the Atmosphere and the Law of Extinction 



of the Solar Rays in passing through it. By James D. Forbes, 



F.R.S. &c. — By the Author. 



The following Donations to the Museum were presented — 



Specimens of the Hypci'stcne Rocks of the Cullin Hills, and of the 

 Limestone and Dykes traversing the Cullen Hills at Kilbride, 

 Isle of Skye. Collected by G. Bellas Greenough, Esq. — Pre- 

 sented by Lord Greenock. 



Specimens of the Calcareous Formation of the Bai-mudas and Baha- 

 ma Islands. Collected by Lieut. -Colonel Enimett, R.E. — 

 Presented by Lord Greenock. 



Monday, 2>d April 1843. 



Sir T. MAKDOUGALL BRISBANE, Bai't., President, 



in the Chair. 



The following communications were read : — 

 1. Chemical Observations on the Flowers of the Camellia Ja- 

 ponica, Magnolia Grandiflora, and Chrysanthemum Leu- 

 canthcmum, and on three Proximate Principles which 

 they contain. — Conclusion. 13y Dr Hope. 

 The autiior first called tlie attention of'tho meeting to the principal 

 facts whicli lie iiad established in the two memoirs read to the Society 

 in the year 1836. 1st, Of these the most important are, that when 

 acids cause a red colour, and alkalis a green or yellow, in a blue 

 vegetable infusion, they act on different substances ; — the acids on 



