42 REPORT OF THE SECRETARY. 



tuted by members of the Academy of Natural Sciences of Philadelphia, 

 and in cooperation with these, a circular has been issued by the Insti- 

 tution, asking for statistics relative to the place of birth, country of 

 parentage, profession or occupation, age, height, and weight of native- 

 born American citizens. To this circular about one hundred answers 

 have been returned from our meteorological correspondents, the whole 

 series furnishing the facts relative to about two thousand individuals. 

 It is intended to present the statistics thus obtained to the author of 

 the memoir above mentioned, as well as to the Academy of Sciences. 

 It will, however, be evident, on reflection, that the value of such sta- 

 tistics must depend on the number of cases which they include, and 

 the length of time through which they are continued ; since it is highly 

 probable that the changes produced by climate and other conditions of 

 existence, become marked only after a succession of generations have 

 been exposed to the modifying influences. 



The Institution continues to receive from time to time, information 

 respecting the existence of mounds and other remains of the original 

 inhabitants of this continent not previously described, and since the 

 proposition has been entertained of preparing a map to illustrate the 

 relative distribution of these remains, all information of this kind will 

 be very acceptable. 



A paper has been some time in possession of the Institution, on 

 the mining operations of the ancient inhabitants of the region around 

 Lake Superior, but it is not yet in a sufficiently elaborate condition to 

 be presented to the public through the Smithsonian Contributions. We 

 hope, however, that in the course of the year we shall be able to have 

 it revised and prepared for the press. It may be proper also to men- 

 tion, in this connection, that a large number of crania of different 

 tribes of Indians, as well as of different races of men, has been collected 

 together at the Institution, the study of which would probably furnish 

 some new facts of interest to the ethnologist. 



Magnetic Observatory . — It was stated in the last report that, as the 

 changes in the direction and intensity of the magnetic force at Toronto 

 were found to be almost precisely the same as at Philadelphia and 

 Washington, it had therefore been concluded that more important 

 service could be rendered science by making the observations at a 

 greater distance from Toronto than the grounds of the Smithsonian 

 Institution. In accordance with this conclusion, the instruments of 

 the observatory, jointly supported by the Smithsonian Institution and 

 the Coast Survey, have been sent to Key West, where the United 

 States government has a fortification, and the Coast Survey maintains 



