CONTENTS. 



On the Compensation Mercurial Pendulum of Mr. Gavin Lowe, 



102 



Remarks on Madeira, Climate of the Tropics, Trade JVinds, Rio 

 Jansiroythe Polar Ice,^c 107,194 



Experiments on the Gas from Coal, chiefly with a view to its 

 practical Application. .. .. .. .. 117,164 



Free Remarks on the Geological JVork of Mr. Greenough. 127 



On the Effect of Fapour on Flame HO 



Occultationof a fixed Star ly Jupiter. .. .. .. 143 



On Mr. Troughton's Expedient for correcting Errors arising 

 from the Excentricity of the Point round ivhich the Indexes 

 revolve in Reflecting Circles. .. .. .. .. 161 



First Report of the Commissioners appointed to consider the Sub- 

 jects of JTeights and Measures. .. .. .. 172 



Observations on certain free Remarks ly Mr. Farey published 

 in the Philosophical Magazine J or August. .. .. 205 



A neio Theory (f Galvanism, supported by sojne Experiments 

 and Observations made by means of the Calorimotor, a new 

 Galvanic Instrument ; also, a new Mode of decomposing Pot- 

 ash extemporaneously . . , . . . . . . 206 



On Friction in Machinery . .. .. ,. ..215 



On poisonous Tea-Leaves, .. .. .. ..218 



On the Geology of Loch Leven in Scotland. . . . . 220 



Remarks on Mr. Meikle's Paper on finding the Longitude by 

 Lunar Observations. .. .. .. ,. ..241 



An Essay on Dreaming, including Conjecltires on the proximate 

 Cause of Sleep v 252,324 



Principles offindbig the Longitude. . . . , . . 265 



Researches on some important Points of the Theory of Heat. 267 



On Irregularities observed in the Direction of the Compass Needles 

 of H. M. SS. IsABiiLLA and Alexander, in their late Voyage 

 of Discovery, and caused by the Attraction of the Iron con- 

 tained in the Ships. . . . . . . . . . . 276 



On the Anomaly in the Variation of the Magnetic Needle as ob- 

 served on Ship-board, . , . , , , . . 282 



