ii CONTENTS. 



Scientific News, 75.— Reward of Twenty Pounds for the Artificial Produ6lfo« 

 of Palladium, ib. — Letter from Lahmde on the Meafure of a Degree of the 

 Earth in Lapland, 76. — Letter from Profeflor Proult to J. C.-Delanietherie on 

 a dangerous fulminating Powder, 77. — Letter from a Correfpondent on the 

 Expediency of converting Foreign Weights and Meafure s into Eng^lifli, ib. 



Account of New Books, 79. — A Syftem of Theoretic and Practical Chemiftryi 

 in Two Volumes, with Plates. Bv Frederick Accum, if .—A pra6lical Effay 7 

 on the Analyfis of Minerals, ib. — A general Hiltory of Mathematics, from the ' , 

 earlieft Times, to the Middle of the^Eighteenth Century, 80. 



FEBRUARY, 1804. 



Engravings of the following Objefls : 1, 2. Two Plates exhibiting the Means of 

 completing the Apparatus for fupplying Worm-Tubs, Sec, with Water, on 

 the Syphon Principle, by Sir A. N. Edelcrantz; 3, 4. Two Plates to ihew the 

 Conftru6lion of a fimple Repeater for the Hours and Quarters, by the Inventor 

 Mr. J. M. Elliot J 5. Diagram to illultrate the Inveftigations of the Figure of 

 the Earth, by Profeflbr Playfair; 6. An improved Chemical Furnace, by R. 

 Chenevix, Eiq. F. R. S. ; 7. Figures to illuftrate an Improvement in Spec- 

 tacles, by W. H. Wollafton, M. D. F. R. S. 



I. Defcrlption of an Apparatus, by which the EfFe<5V of Atmofpheric Preflure In 

 fupplying Worm-Tubs and other Veflels with Water on the Syphon Prin- 

 ciple, may be fecured againft any Interruption to be caufed by the extricated 

 Air. In a Letter from Srr A. N. Edelcrantz, Counfellor of the Chancery, 

 and Private Secretary to the King of Sweden, Member of the Swedilh 

 Academy, &c. &c. - . , - . Page 81 



II. Enquiries concerning the Nature of a Metallic Subftance lately fold in 

 London as a new Metal, under the Title of Palladium. By Richard Chenevix, 

 Efq.F.R. S. andM.R.I.A. - - - - - 83 



III. Invcftigation of certain Theorems relating to the Figure of the Earth. 

 By John Playfair, F. R. S. Edin. and Profeffor of Mathematics in the Uni- 

 verfity of Edinburgh. ------ 102 



IV. On the Determination of the Length of the Solar Year. By Mr. R. Win- 

 ter. - - - * - - -- 116 



V. Extrafl from a Letter of R. Chenevix, Efq. F. R. S. from Drefden, to 

 Charles Hatchett, Efq, F. R. S. containing Information refpefling the new 

 Metal contained in Crude Platina j Beet Sugar j the Non-Exiftence of Aguf- 

 tite as a peculiar Earth ; and a Defcription of a new Furnace for Chemical 

 Operations. Communicated by C. Hatchett, Efq. '- - 117 



-Vl. Account of an Experiment to imitate the Damafcus Sword Blades. In 

 a Letter from Mr. James Stodart. - - - - 120 



VII. Letter from a Correfpondent on the Effects of Thuader on fermenting Li- 

 quids} the Chemical Aftion of Sound, and Tremulous Motions j with other 

 Obfervations. - - - - - - 122 



VIII. Improvement of the Electrical Machine, chiefly with Refpe6l to the 

 Rubbers; by Mr. Wolff, of Hanover. - - - 124 



IX. On the Cultivation of the Sun-flower, and its Advantages. 128 



X. Chemical Examination of a new Vegetable Salt, and of a new Acid dif- 

 coveredinit: by Klaproth. - - - - - 129 



XI« On Mr. Woolf's Invention for equalizing the Aftlon of a Crank, m 

 Contradiftlnflion to the Effe6l of the Fly, in producing an uniform Effeft 

 againft a variable Refiftance. In a Letter from Mr. T. Jones. 133 



XII. Obfervations on the extinft Volcanoes in the Environs of Coblentz, by 

 the Chevalier de Sade. Tranflated from the original Manufcript, communi- 

 cated by the Count de Bournon. - - - - 135 



XIII. On an Improvement in the Form of Spe61:acle-Glaflres, by William Hyde 

 Wollafton, M. D. F. R. S. Communicated by the Author. - 143 



XIV. Letter of Enquiry concerning a Gun to throw double-headed Shot i with 

 the Editor's Reply. - - - - - - 146 



XV. Prognoftics of the Weather, eftablirtied by long-continued Obfervation 

 upon the Conduft and Appearances of Birds, Beafts, Inltils, Plants, Meteors, 

 the Heavenly Bodies, Minerals, &;c. Communicated by a Coireifondent, 148 



XVI. A 



