CONTENTS. 



SCIENCE. 



ART. 



PAGE. 



IV. On a new Barometric Formula for Afountain Heights, in which the 

 Hygrometric Condition of the Atmosphere is systematically consi- 

 dered. By Henry Laus Renny, M.R.I. A., Lieutenant, Royal 



Engineers, Retired List. Eead January 8, 1855 437 



V. On the Drainage of Haarlem Lake. By Samuel Downing, LL.D., 

 M.R.I. A., Professor of Civil Engineering in the University of Dublin. 

 Read February 12, 1855 449 



VI. On the Degree of the Surface reciprocal to a given one. By George 

 Salmon, D. D., M.R.I.A ., Fellow of Trinity College, Dublin. Read 

 November 30, 1855 461 



VII. On the Molecular Formation of Crystals. By Robert T. Forster, 



B.A. Read May 14, 1855 '439 



VIII. Experimental Researches on the Lifting Power of the Electro-Magnet. 

 Part III. By T. R. Robinson, D.D., M.R.LA., F.R.S., tjc, (^c. 

 Read November 30, 1857. . - 501 



IX. On the Determination of the Intensity of the Earth's Magnetic Force 

 in absolute Measure, by means of the Dip-Circle. By Humphrey 

 Lloyd, D.D., D.C.L., F.R.SS.L. ^ E. ; V.P.R.LA.; Corre- 

 sponding Member of the Royal Society of Sciences at Gottingen ; 

 Honorary Member of the American Philosophical Society, of the Ba- 

 tavian Society of Sciences, and of the Societe de Physique et d'His- 

 toire Naturelle of Geneva, ^c, Sfc. Read January 11, 1858. . .535 



VOL. XXIIL b 



