CONTENTS OF VOLUME XVIII 



J 



NUMBER I. 



Page . 



Art. I. Of the Phenomena and Causes of Hail Storms. By 



Professor Demson Olmsted, - - - - 1 

 II. Architecture in the United States, - - . - 11 



III. Sketch of a Classification of the European Rocks; bj 



Henry T. De la Beche, Esq. F. R. S. <^c. - - 26 



IV. On the Rectification of the Ellipse; by C. Wilder^ 38 



V. Notices and Observations on the American Cicada, or 



Locust; by Dr. S. P, Hildreth, - - - 47 



VI. The Gold of the Carolinas in Talcose Slate; by 



Prof. Eaton, - - - - - - - 50 



VIL On the Office of the Nitrogen of the air, in the process 



of Respiration ; by Prof Lewis C. Beck, M. D. - 52 



VIIL Notice of Animalcules In Snow; by Dr. Joseph E. 



XIX. On the Sulphate of Strontian, Kingston, (U- C); with 



notices of the Geology of the vicinity; by Lieut. 

 Baddeley, ------- 



XX. On the Vegetation of the First Period of an Ancient 



World ; by Henry Witham, of Lartington, (Eng.) 



F. G. S. &c. 



XXL On the use of the Anthracite Coal in the making of 



56 



58 



J Muse, 



t ^ IX. The Iodide of Potassium, (Hydriodate of Potassa of 



- ' the shops,) as a test for Arsenic; by Prof J. P. 



ui . Emmet, Univ. Virgin. . - - . , 



^i^ X- On the Dew Point; by A. A. Haves, - - - 63 



\^ XL On the cause of the peculiar aspect of the air, in the 



Indian Summer, - - ' - - - - 66 



XII. Solution of a Problem in Fluxions; by Prof Theo- 

 dore Strong, -------67 



XIII. On capillary attraction ; by Prof Theodore Strong, 70 



XIV. Particulars respecting an irised Aurora Borealis ; by 



James Bowdoin, Esq. ------ 72 



XV- Notice and description of a Marine Ventilator; by 



Samuel Whiting, - - - - - -75 



XVL Notice of some Localities of Minerals, near Baltimore, 



Md, ; by Philip T. Tyson. With an Appendix, by 

 C. U. Shepard, ------ 78 



XVII. On the Crystalline Form of Iodine; by Lieut. W, W. 



Mather, Assist, Prof of Chem, and Min. U» S. Mil- 



Acad. W. P. 84 



XVIIL On the Transition Rocks of the Cataraqui ; by Capt. 



R. H. Bonnycastle, R. E. Canada, - - - , 85 



104 



110 



Brick; by William Meade, M. D- - - - 118 



