48 REPORT OF, TME SECRETARY. 
air from the halls of Congress, &c., from which a report is to be 
made, under the direction of the Institution, on the ventilation of the 
public buildings of this city. 
The most important publications under this head are the researches 
relative to electric currents, by Professor Secchi; on the explosibility 
of nitre, by Dr. Hare; on the ammonia-cobalt bases, by Drs. Gibbs 
and Genth; and on astronomical photography, by Dr. Henry Draper. 
A valuable report on recent improvements in the chemical arts by 
Booth & Morfit was published in 1852, and there have been given in the 
annual reports of the Institution a series of translations and articles 
presenting a view of the progress of physics and chemistry from 
year to year, since 1853, among which we may particularly notice 
the translation of Miller on recent contributions to electricity, and 
the reprint of Powell on Radiant Heat. 
Terrestrial magnetism.—The subject of terrestrial magnetism has 
been prosecuted simultaneously with that of meteorology, and an 
observatory was erected in the Smithsonian grounds, fitted up with 
the most approved instruments, and conducted under the joint 
auspices of the Institution and of the Coast Survey. After remain- 
ing in operation for several years, the instruments were transferred 
to Key West, as a remote station where observations were still more 
desirable. Instruments were also furnished an expedition to Mexico, 
and used with much success by Mr. Sonntag, whose results were 
published in the Smithsonian Contributions to Knowledge. Appa- 
ratus was also furnished to Dr. Kane, Dr. Hayes, and other explorers, 
by means of which valuable results were obtained. 
Of the more important publications of the Institution, which have 
tended to advance this science, may be mentioned the articles by 
Dr. Locke, on the dip and intensity; the elaborate discussion, by 
Professor Bache, of the magnetic observations made at Girard College 
from 1841 to 1845; the report on magnetical observations in the 
arctic seas by Dr. Kane, reduced at the expense of the Institution 
by Mr. C. A. Schott, and those made in Pennsylvania and adjacent 
States by Professor Bache, and in Mexico by Mr. Sonntag. 
Explorations.—In the deficiency of means for more extended oper- 
ations, as has been frequently represented in the annual reports, the 
efforts of the Institution in the line of explorations and collections are 
confined, as strictly as possible, to America; but within this limit 
there are few regions which have not furnished scope, in some form, 
to its activity. Arctic America, all the unknown portions of the 
