CONTENTS, V 



■ 



50- Meteorological Observations, . . • • . 



51, 52, 53. Note to Dr. Hildreth's article in Vol. xxix. of this 

 Journal — Eyes of flies changed to red by nitric acid — Death 

 of Mr. David Douglas, . . . . . ... 



54. List of new publications, 



Page. 



194 



196 

 198 



APPENDIX. 



On the collection of geological specimens and on geological sur- 

 veys ; by Charles T. Jackson, . . 

 Confirmation of Judge Woodruff's account of the influence of the 



203 



William R. Morris, . . 208 





NUMBER II. 



Art. I. Observations on the Comet of Halley, made at Yale Col- 



lege; by Elias Loomis, . 

 II. Observations on the Variation of the Magnetic Needle, 

 made at Yale College, in 1834 and 1835; by Elias 



209 



Loomis, . .♦ . .,. •• • 221 



III. On the Transition Rocks of the Cataraqui ; by Capt. R. 



H. Bonnycastle, R. En. . 



IV. Theory of the Variations of the Arbitrary Constants in 



233 



Elliptic Motion ; by Prof. Theodore Strong, . 248 



V. On Definitions ; by Rev. D. Wilkie, . . . 266 



275 



VI. On the Formation of Compound or Twin Crystals ; by 



James D. Dana, . . . .... 



VII. On the late efforts in France and other parts of Europe 



to restore the Deaf and Dumb to hearing; by George 

 E. Day, late Instructor in the New York Institution 



for the Deaf and Dumb, 301 



VIII. On an instrument proposed for measuring the expansion 



of Solid Bodies, and which may also be used as a Ther- 

 mometer; by Lieut. W. W. Mather, U. S. Army, 324 

 IX. Notice of a Scientific Expedition ; by Prof. E. Emmons, 330 

 X. On two American Species of the Genus Hydrachna ; by 



James D. Dana and James Whelpley, . . . . 354 

 XI. On the Resistance of Fluids, in reply to Professor Keely, 



with remarks on the measure of Mechanical Power ; by 



Eli W.Blake, . . . . , • . .359 



