Miscellanies. 369 



Place of Observation. 



Brooklyn, N. Y. . . . 



New Haven, Conn. . 

 Southwick, Mass. . . 



Wesleyan University, Conn. 



"Williamstown College, Mass. 

 Dorchester Observatory, Mass. 



The committee to vs^hom vi^as referred the paper of Prof. Loomis, 

 entitled "Additional Observations of the Magnetic Dip in the United 

 States," reported in favor of its publication, and which was ordered 

 accordingly. These observations are incorporated in Art. V. of this 

 Vol., p. 41. 



The committee, consisting of Dr. Hare, Dr. Bache, and Mr. Booth, 

 on a paper entitled " On a new compound of deutochloride of plati- 

 num, nitric oxide, and hydrochloric acid ; by Henry D. Rogers, 

 Professor of Geology in the University of Pennsylvania, and Martin 

 H. Boye, Graduate of the University of Copenhagen," reported in 

 favor of publication in the Transactions of the Society. The publi- 

 cation was ordered accordingly. 



This substance is procured by dissolving platinum in an excess of 

 nitromuriatic acid, and evaporating nearly to dryness ; after which it 

 is treated with aqua regia, freshly prepared, from concentrated hy- 

 drochloric and nitric acids. A little water is afterwards added, drop 

 by drop, just sufficient to keep the chloride of platinum dissolved, 

 when the compound will remain in the form of a gamboge yellow 

 powder. It is then separated by decanting and filtering, and pressed 

 between the folds of bibulous paper, and dried in vacuo over sulphu- 

 ric acid. 



The precipitate is a yellow, minutely crystalline powder, which ab- 

 sorbs water with great avidity. It may be preserved, without decom- 

 position, in dry air, or in vacuo. It is decomposed by water, alcohol, 

 &c., with extrication of nitric oxide, chloride of platinum remaining 

 in solution. A concentrated solution of chloride of platinum has, 

 however, no action on it. Heated in an atmosphere of hydrogen, it 

 gives off a large amount of chloride of ammonium, leaving a residu- 

 um of metallic platinum. 



Analysis. — The salt analyzed, was prepared and kept in the man- 

 ner described. Heated to the temperature of 212° F., it does not 



