CONTENTS of N° 18.— New Series. 



LXII. On the Artificial Production of Cold. By Richard 



Walker, Esq., of Oxford. ( With a Plate.) .... page 401 



LXIII. On the Causes of Single and Erect Vision. By L. M. S. 406 



LXIV. On the Reaction of Effluent Water, and on the Maximum 

 Effect of Machines. By Mr. P. Ewart. With Notes relating to the 

 Theory of Barker's Mill. By J. Ivory, Esq. M.A. F.R.S 416 



LXV. On the Figure of the Earth, as deduced from Measurements 

 of the Meridian. By J. Ivory, Esq. M.A. F.R.S 431 



LXVI. On the characteristic Equation of Curve-surfaces capable 

 of being evolved in a Plane. By M. Fayolle 436 



LXVII. Proceedings of Learned Societies :— Royal Society; 

 Linnsean Society ; Geological Society; Astronomical Society; Pro- 

 ceedings at the Friday-Evening Meetings of the Royal Institution 

 of Great Britain 436-456 



LXVIII. Intelligence and Miscellaneous Articles :—- Origin of 

 Trap Rocks; Analyses of Tourmalines; Prof. Stromeyer's New 

 Method of separating Manganese from Lime and Magnesia ; Sin- 

 gular Action of Phosphoric Acid on Albumen; List of Earthquakes 

 which occurred in 1827; Red Rain supposed to arise from Butter- 

 flies ; Weather in Paris ; MM. Dumas and Boullay's Analysis of 

 Alcohol, iEther, &c. ; Test of the Presence of Ammonia ; List of New 

 Patents; Scientific Books; Meteorological Observations ; Table, &c. 



458—469 



Index : * 70 



• * It is requested that all Communications for this Work may be addressed, 

 post paid, to the Care of Mr. R. Taylor, Printer, Red- Lion-Court, Fleet- 

 Street, London. 



