CONTENTS. 



Comparison of Mr. Ivory's Table of Refractions, Philosophical 

 Transactions 1824, ttvV/i Z);-. Bradley's Observations pub- 

 lished in M. Bessel's Fiindamenta Astronomice, pp. 53, 54. 

 % J. Ivory, Esq. M.A. F.R.S. 107 



Anali/sis of the Water of the Rio Vinagre, in the Andes of Po- 

 payan, by M. Mariano de Rivero; to//// geognostic and 

 phj/sical niiistrations of some Phccnoinetia which are exhibited 

 by Sulphur, Sulphuretted Hydrogen, and Water, in Volcanos. 

 By M. A. DE Humboldt 108 



On the Nature and Properties of Indigo ; with Directions for the 

 Valuation of different Satnples. By John Dalton, Esq. 

 F.R.S. S)r 122 



On Aerial Navigation. By A Correspondent. . . 128 



On Mr. Sturgeon's Suggestion relative to the Electric and 

 Magnetic Causes of the Earth's Motion, and on its Similarity 

 to the Theory of Mr. W. Herapath. By Mr. J. P. Bevan 



179 



Demonstrations of Trigotwmetrical Formtdce. By A Corre- 

 spondent 181 



A nev: Binary Arrangement of the Macrurous Crustacea. By 

 K. U. U^vfOKTH, Esq. F.L.S. 8iC 183 



On the Geology and Topography of the Island of Sumatra, and 

 some of the adjacent Islaiids. By the late William Jack, 

 M.D.M.G.S. 185 



On the Structure of the Tarsus in the Tetramerous and Trimerons 

 Colcoptera of the French EntomologisH. By the Rev. W. 

 KiKBY, M.A. F.R.S. Sf L.S.8fc 193 



On the Use of Analysis in investigating the Elemcntaty Relations 

 of Figure and Forces. ^?/ A Correspondent. . . 195 



Method of extracting Titanium from Minerals, and qfseparatittg 

 it completely frotn the Substances with which it is found com- 

 bined. By M. Peschier 200 



Additional Experiments and Observations on the Application of 

 Electrical Combinations to the Preservatiofi of the Copper 

 Sheathing of Ships, and to other Purposes. By Sir Humphry 

 Davy, Bart. P.R.S 203 



Observations on the Application of Machinety to the Computa- 

 tion of Mathematical Tables. By Charles Babbage, Esq, 

 F.R.S. Sfc. SiC 207 



On the Theory of the Figure of the Earth. By J. Ivory, Esq. 

 M.A. F.R.S 24-1 



Correction of an Inadvertence in a Geodetical Problem inserted 

 in the Philosophical Magazine for July last. By J. Ivory, 

 Esq. M.A. F.R.S. . ........... Qi9 



Obscrvatioiis on Locomotive Action, with reference to its Dif- 

 ferences in Skaiting and Walking. By A Correspondent 



250 



