VoL.6l. Philosophical Magazine. April 1823. 



Contents of Number 300. 



Lll, On Electro-Magnetism. By Mr. J. Tatum Page 241 



LIII. True appai'ent Right Ascension of Dr. Maskelyne's 36 

 Stars for every Day in the Year 1823, at the Time of passing the Me- 

 ridian of Greenwich 245 



LIV. Queries relative to the Mode of using M. Schumacher's 

 Tables of Aberration and Nutation ^ . . . 248 



LV. On the late Opposition of the Planet Vesta. By S. Groom- 

 BRTDGE, Esq. F.R.S. &c. &c 249 



LVI. Observations on the Experiments of Mr. Murray on the 

 supposed Relation between Caloric and Magnetism. By An Expe- 

 rimenter 251 



LVII. On the Cause of the Magnetic Power of the Poles of the 

 Earth. By Mr. William Dobbie 252 



LVIII. Description of the Methods employed in determining the 

 Altitudes of several of the principal Mountains and other remarkable 

 Objects visible from the Trigonometrical Station on Rumbles Moor, 

 Yorkshire. By A Correspondent 255 



LIX. Inquiry relative to the Catalogue of Zodiacal Stars 265 



LX. Announcement that a Discovery has been made which will 

 render Pot- and Pearl-ashes no longer indispensable to Bleachers. 

 By Gavin Inglis, Esq 265 



LXI. Proposal for a new Method of determining a Fixed Unit of 

 Measure, by deducing the same from the Curvature of the Earth. By 

 James Boaz, Esq. of Glasgow 266 



LXII. Abstract of an Essay by M. Girard " on the Resistance of 

 Cast-Iron in relation to its Use for Conduit Pipes, and the Boilers of 

 Steam-Engines." Communicated by Mr. Tredgold 270 



LXIII. On Encke's Comet 275 



LXIV. Sketch of a Course of Lectures on Metallurgy delivered at 

 the London Institution, February 1823. By John Taylor, Esq. 

 Treasurer of the Geological Society 283 



LXV. Notices respecting New Books : Analysis of Periodical 

 Works on Zoology and Botany 292-302 



LXVI. Proceedings of Learned Societies 303-31 3 



LXVII. Intelligence and Miscellaneous Articles:— Mr. Perkins's 

 Steam-Engine. — Condensation of Gases into Liquids. — Mr. Telford's 

 Report on London Bridge.— New University in Virginia. — Natural 

 History Society of Auvergne — Volcano. — Earthquakes. — List of 

 New Patents.— Meteorological Table 313-320 



*^* Communications for this Work, received by the Editors, 

 38, Shoe-Lane, will meet with every attention. 



RICHARD TAAoR, printer, SHOE-LANE, LONDON. 



