ADVERTISEMENT. 



The object of the (teneral Appendix to the Annual Report of the 

 Smithsonian Institution is to furnish brief accounts of scientific dis- 

 covery in particuhu- directions; reports of investigations made by 

 colhiborators of tlie Institution; and memoirs of a general character 

 or on special topics that are of interest or value to the numerous 

 correspondents of the Institution. 



It has been a prominent object of the Board of Regents of the 

 Smithsonian Institution, from a very early date, to enrich the annual 

 report required of them by law with memoirs illustrating the more 

 remarkable and important developments in physical and biological 

 discovery, as well as showing the general character of the operations 

 of the Institution; and this purpose has, during the greater part of its 

 history, been carried out largely by the publication of such papers as 

 would possess an interest to all attracted by scientific progress. 



In 1880 the Secretary, induced in part by the discontinuance of an 

 annual summary of progress which for thirty years previous had been 

 issued by well-known private publishing firms, had prepared by com- 

 jDetent collal)orators a series of abstracts, showing concisely the prom- 

 inent features of recent scientific progress in astronomy, geology, 

 meteorology, physics, chemistry, mineralogy, botany, zoology, aiid 

 anthropology. This latter plan was continued, though not altogether 

 satisfactorily, downi to and including the year 1888. 



In the report for 1889 a return was made to the earlier method of 

 presenting a miscellaneous selection of pages (some of them original) 

 embracing a considerable range of scientific investigation and discus- 

 sion. This method has been continued in the present report for 1904. 



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