Vol.62. Philosophical Magazine. July 1823. 



Contents of Number 303. 



I. An Essay on tlie Question, Whether there be two Electrical 

 Fluids according to Du Faye, or one according to Franklin. By 

 Robert Hare, M.D. Professor of Chemistry in the University of 

 Pennsylvania Page 3 



II. Description of an Electrical Plate Machine, the Plate mounted 

 horizontally, and so as to show both negative and positive Electricity. 

 Illustrated by Engravings. By Robert Hare, M.D. Professor of 

 Chemistry in the University of Pennsylvania 8 



III. Description of an improved Blowpipe by Alcohol, in which 

 the Inflammation is sustained by opposing Jets of Vapour, without a 

 Lamp ; also, of the Means of rendering the Flame of Alcohol com- 

 petent for the Purpose of Illumination. Illustrated by an Engrav- 

 ing. By Robert Hare, M.D. Professor of Chemistry in the Uni- 

 versity of Pennsylvania 9- 



) IV. Remarks on the Trisection of a Circular Arc. By Mr. Paul 

 Newton 10 



V. On a Method of observing Solar Eclipses by means of the Al- 

 titude and Azimuth Instrument. By A Correspondent 15 



VI. True apparent Right Ascension of Dr. Maskelyne's S6 

 Scars for every Day in the Year 1823, at the Time of passing the 

 Meridian of Greenwich IQ 



\'\l. On Metallic Titanium. By W. H. Wollaston, M.D. 

 V.P.R S IS 



VIII. Report of Thomas Telford, Esq. on the Effects which 

 will be produced on the River Thames by the Rebuilding of London 

 Bridge 21 



IX. Observations on the Project of taking down and rebuilding 

 London Bridge 28 



X. An Account of the Observations and Experiments on the Tem- 

 perature of Mines, which have recently been made in Cornwall, and 

 the North of England; comprising the Substance of various Papers 

 on the Subject lately published in the Transactions of the Roj'al Geo- 

 logical Society of Cornwall, and other Works 38 



XL The Third Portion of a Catalogue of Zodiacal Stars for the 

 Epoch of January 1, 1800; from the Works of Herschel, Piazzx, 

 Bode, and others; with illustrative Notes. Selected and arranged 

 by a Member of the Astronomical Society of London 47 



XH. Observations on M. Laplace's Communication to the 

 Royal Academy tif Sciences, " Sur I'Attraction des Spheres, et sur 

 la Repulsion des Fluides clastiques." By John Herapath, Esq.. . 61 



XIII. Notices respecting New Books : Palmer on a Railway of a 

 new Principle — Dr. Ure's Dictionary of Chemistry .-. . 66-69 



XIV. Proceedings of Learned Societies : Geological Society. — 

 Royal Academy of Si;iences of Paris 70-72 



XV. Intelligence and Miscellaneous Articles: — Mr. Murray, On 

 tlie Combination of Phosphorus with Sulphuret of Carbon as con- 

 nected with an instantaneous Light, &c, ; and on the Influence of 

 Heat on Magnetism, &c. — Acid Earth of Persia — Varieties of the 

 Lynx in the North of Europe, — Mr. Belzoni's Progress in Africa. 

 —OBITUARY: Lieut.-Col. William Lambton. — List of New 

 Patents. — Meteorological Table 73-80 



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

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



