CONTENTS. V 



Page. 



VIII. On Water Spouts; by Prof. Hans Christian (Ersted, 250 

 IX. Brief notice of the extrication of Barium, Strontium 

 and Calcium by exposure of their chlorides to a 

 powerful voltaic circuit in contact with mercury as 

 a "cathode;" and the distillation of the resulting 

 amalgams by means of vessels of iron, . . 267 



X. Process for a Fulminating Powder — for the Evolution 

 of Calcium and Galvanic Ignition of Gunpowder ; 



by Dr. Hare, 268 



XI. On the Boracic Acid Lagoons of Tuscany ; by John 



Bowring, LL. D 270 



XIL Magneto-Electric Multiplier; by Chas. G.Page, M- D., 275 



XIII. Method of adjusting the Dipping Needle ; by Prof. 



Thomas H. Perry, ...... 277 



XIV. Results of Experiments on the Vibrations of Pendulums 



with different suspending springs ; being the sub- 

 stance of a paper by W. J. Frodsham, F. R. S., . 278 

 XV. On Coins and Medals, with a notice of the Medal which 

 has been recently struck to commemorate the settle- 

 ment of New Haven, Connecticut, . . • 285 

 XVI. Formula for discovering the Weight and Volume in a 



Mixture of two Bases ; by Dr. Jno. M. B. Harden, 289 



XVII. Abstract of a Monograph of the Genus Sciurus, with 

 descriptions of several new species and varieties ; 

 by J. Bachman, M. D., . . . , . 290 



XVIII. Catalogue of Botanical Specimens, collected by J. 

 Wolle and A. L. Httebener, during the year 1837, 

 in the vicinity of Bethlehem and other parts of 

 Northampton County, Pennsylvania, in the order as 

 they were found in bloom, ..... 310 

 XIX. Effects of Lightning upon the packet ship New York ; 



by Mr. Charles Rich, ..... 321 

 XX. Report on the Shooting Stars of August 9th and 10th, 

 1839, with other facts relating to the frequent occur- 

 rence of a meteoric display in August; by Edward 

 C. Herrick, 325 



XXI. Description of a New Species of Liatris ; by David 



Thomas, 338 



XXII. Observations on the New Haven Tornado of July 31, 



1839 ; by Prof. Denison Olmsted, . . ,340 



