CONTENTS. iii 



MARCH 1803. 



Engravings of the following Objeas : 1. Figures illuftrative of Dr. Wollafton's. 

 Theory of the oblique Refraftion of Iceland Cryftals j 2. Mr. Dalton's Sketch 

 of the Rivers of England and Wales, and the Diftri&s which fupply them 

 with Water; 3. Figure to illuftrate Mr. Gough's theory of fonorous Undula- 

 tion; 4. The Craniognomic Syftera of Gall; 5. An Inftruraent for extracting 

 hard Bodies out of the OEfophagus. 



I. Comparative Experiments and Obfervations on^ Myrtle Wax, Bees Wax, 

 Spermaceti, Adipocire, and the Cryftalline Matter of biliary Calculi. In a 

 Letter from John Bollock, M. D. - - - - Page 129 



II. On the Nature of Mufical Sounds. In Reply to Dr. Young, By Mr. John 

 Gough. --------139 



III. Obfervations on the two lately discovered celeftial Bodies. By William 

 Herfchel, LL. D. F.R. S. 142 



IV. On the oblique Refraaion of Iceland Cryftal. By William Hyde Wollafton, 

 M. D. F.R. S. From the Phil. Tranf. for 1802. - ' - . 148 



V. The Theory of Compound Sounds. By Mr. John Gough. - 152 



VI. Experiments and Obfervations to determine whether the Quantity of Rain 

 and Dew is equal to the Quantity of Water carried off by the Rivers and raifed 

 by Evaporation j with an Enquiry into the Origin of Springs. By Mr. John 

 Dalton. - - - - - - - 159 



VII. Defcription of an Inftrument for extraaing Hard Subflances which may- 

 flick during their PafTage to the Stomach. By G. C. - - 175 



VIII. On the Flexure of Wax and other Bodies by irregular cooling, with Con- 

 fiderations on the Probability that it may be caufed by the Law of Cryftalliza- 

 tion. In a Letter from R. B. - - - - - 175 



IX. An Account of fome Cafes of the Produaion of Colours, not hitherto 

 defcribed. By Thomas Young, M.D. F. R. S. F. L. S. Profeffor of Natural 

 Philosophy, in the Royal Inilitution. - - - - 180 



X. A Memoir on the Wax Tree of Louifiana and Pennfylvania. By Charles 

 Louis Cadet, of the College of Pharmacy at Paris. - 187 



XI. Outline of the Craniognomic Syftem of Dr. Gall, Phyfician at Vienna. Bv 

 Dr. Bojames. ------- i9f 



Scientific News, Account of Books, &c— Account of Ventriloquifm— Afcent of 

 Mont Blanc and Mont Perdu—Experiment on Sound— Evaporation of Water 

 at an elevated Temperature. - - - - 202 to 207 



APRIL 



