CONTENTS OF VOL. XXVIII. — THIRD SERIES. Vll 



Page 



Note by Mr. T. Hopkins on his Paper on the Semi-diurnal Fluc- 

 tuations of the Barometer 41 G 



On some new Compounds of Perchloride of Tin, by M. Lewy. . 416 

 Analysis of two species of Epiphytes, or Air Plants, by John 



Thomson, A.M 420 



Analysis of Ceradia furcata Resin, by Robert D. Thomson, M.D. 422 



Meteorological Observations for March 1846 423 



Table 424 



NUMBER CLXXXIX.-JUNE. 



Dr. D. P. Gardner's Researches on the Functions of Plants, 

 with a view of showing that they obey the Physical Laws of 

 Diffusion in the Absorption and Evolution of Gases by their 

 Leaves and Roots 425 



Dr. C. F. Schcenbein on the relation of Ozone to Hyponitric 

 Acid 432 



Mr. T. Graham on the Composition of the Fire-Damp of the 

 Newcastle Coal Mines « 437 



Dr. J. Stenhouse's Observations on the Resin of the Xanthorcea 

 hastilis, or Yellow Gum-resin of New Holland 440 



Mr. H. Sloggett on the Constitution of Matter 443 



Messrs. Scoresby and Joule's Experiments and Observations 

 on the Mechanical Powers of Electro-Magnetism, Steam, 

 and Horses 448 



Dr. Faraday's Experimental Researches in Electricity. — Twen- 

 tieth Series. — Action of Magnets on Metals generally (con- 

 cluded) 455 



The Astronomer Royal on the Equations applying to Light 

 under the action of Magnetism 469 



The Rev. W. V. Harcourt's Letter to Henry Lord Brougham, 

 F.R.S. &c, containing Remarks on certain Statements in 

 his Lives of Black, Watt and Cavendish 478 



NUMBER CXC— SUPPLEMENT TO VOL. XXVIII. 



The Rev. W. V. Harcourt's Letter to Henry Lord Brougham, 

 F.R.S. &c, containing Remarks on certain Statements in 

 his Lives of Black, Watt, and Cavendish (concluded) 505 



Prof. Owen's Observations on Mr. Strickland's Article on the 

 Structural Relations of Organized Beings 525 



Prof. Marignac's Observations on Messrs. Lyon Playfair and 

 Joule's Memoir on Atomic Volume and Specific Gravity . . 527 



