CONTENTS 



OF THE 



TWELFTH VOLUME. 



I. Description of the Ar/emates of Copper and of Iron. 

 By the Count ^^ Bo u R N o N - Page 3 



II. On preferv'mg Frcfh IVater fweet during long Voyages. 

 JB;/ Samuel Bentham, -E/7. - - la 



III. Di'fcription of a Machine for raijing Hater. By Mr. 

 U, Sx'RJ'EMiVf of IVhitehaven, Cumberland - -,14 



IV. 'Obfervations on the Ipomsea Hifpida, and fom-e other 

 Plants of the Family of the Convolvulus. By Felix 



FONTANA - - ~ r 



V. An Examination of C. Clouet's new Procefs for 

 making Caji Steel from Bar Iron hy means of the Becom- 

 pofttion of Carbonic Acid. i?y D A v I D M U s H E t; Efc/. 

 of the Calder Iron IVorks - - 27 



VI. On the Strength of Acids, as indicated by the Specif c 

 Gravity, ajid by the Areometer of M. Baum^. By Ro- 

 BERt'Einglev, jE/?. King's Affay Majler, Mint; Lon- 

 don - - " ~ 36 



VII. Obfervations on the Plant by which the Indians of Ame- 

 rica preferve themf elves from the Bite of Venomous l<erpents. 

 Communicated to Count RuMFORD by Don Pedro 

 d'Orbies Y Vargas - . " ,. 3'^ 



VI H. Account of a lingular Method of hunting Wild Swine 

 in the Ijland of Sumatra. By Mr. John, Mifionary at 

 Tranquebar - - " . 39 



JX. Inquiries into coloured Light, by a Collation of the 

 Experiments and Obfervations made hy Sir Ifaac Newton 

 on that SubjcB ; togHher with fome additional ones. By 

 Governor Fownall - . ," . 4* 



X. On a new Combination difcovered in 'LafJ'er, which 

 Brugnatelli confidered as the Cobaltic Acid. By C. Dar- 



UACtt - - - " 49 



XI. Method of making Lime cryjlalhze. By Tromms- 

 dorff - - - ■ 53 



XII. Refill t of the Obfervations of the new Star difcovered 

 on the \jl V J^inuary 180X, at the Royal Obfcrvatory of 



VoL.XIL N0.48. a Palermo. 



