THE SMITHSONIAN INSTITUTION. 171 



They will probably be given in due time to the world as a part of the 

 Smithsonian Contributions. 



The investigations mentioned in the foregoing account have been at- 

 tended with very laborious arithmetical calculations. A small appro- 

 priation has been made to defray, in part, the expense of these. Indeed, 

 without the aid thus given, the discoveries we have related would 

 scarcely have been made — at least at this time, and in our country. 



2. The next memoir is A71 account of the discovery of a Comet by Mks 

 Maria Mitchell, of Nantiiclcet, with its approximate orbit, calculated by 

 herself. The honor of this discovery has been duly awarded to the 

 author. A medal has been presented to her by the King of Denmark, 

 and the comet itself is now known to astronomers in every part of the 

 world by her name. From the peculiarities of the case, the Executive 

 Committee recommended that a small premium be presented to Miss 

 Mitchell. 



3. The third memoir is On a new method of solving Cubic Equations, by 

 Professor Strong, of New Bi'unswicJc, New Jersey ; a purely mathemati- 

 cal paper, which has been pronounced an interesting addition to that 

 branch of science. 



4. The fourth memoir is A contribution to the Physical Geography of the 

 United States. It presents a section, from actual surveys, of the descent 

 of the bed of the Ohio river from its source, in the State of New York, 

 to its mouth, on the Mississippi. By a series of observations and elabo- 

 rate calculations, the author exhibits the amount of water which passed 

 down the river during a period of eleven years prior to 1849. This, 

 compared with the amount of rain which fell during the same time on 

 tlie surface drained by the river, gives a series of interesting results in 

 reference to evaporation. 



It also contains a proposition for improving the navigation of the 

 Ohio, founded upon data given in the preceding part of the memoir. 

 Whatever may be the result of the plan here proposed, this memoir has 

 been recommended for publication as a valuable addition to the physi- 

 cal geography of the United States. The author is Charles Ellct, jr., 

 the celebrated engineer of the wire bridges over the Niagara and Ohio 

 rivers. Another memoir is promised by the same author, which will 

 be a continuation of the same subject. 



5. The fifth memoir is contributed by Dr. Robert Hare, of Philadel- 

 phia, and is intended to elucidate the remarkable phenomena exhibited 

 at the great fire in the city of New York on the 19th of July, 1845, 

 during which two hundred and thirty houses were destroyed, containing 

 merchandise amounting in value to sixty-two millions of dollars. " A 

 series of detonations, successively increasing in loudness, were followed 

 by a final explosion, which tore in pieces the building in whicfi it took 

 place, threw down several houses in its vicinity, and forced in the fronts 

 of the houses on the opposite side of the street." These effects were 

 attributed to gunpowder, though the owner of the building in which the 

 explosion occurred declared that none of this article was present, but 

 that the house contained a large quantity of nitre, in connexion with 

 merchandise of a combustible nature. 



This memoir contains a series of investigations relative to the explo- 

 sions which may be produced by heated nitre in connexion with carbon- 



