initlj00iiiiin ^n^tittitirrn. 



PREFACE. 



FoK tlie purpose of facilitating the accurate determination of the geogra- 

 phical position of important points in the IJnited States, the Eegents of the 

 Smithsonian Institution authorized the preparation of lists of occultations 

 and co-ordinates of reduction to particular j)laces for the years 1848 and 

 1849. Congress has, since, ordered the publication of an American JSTautical 

 Almanac ; and, as lists of Occultations will form a regular part of this ephe- 

 meris, Mr. Preston, the late Secretary of the JSTavy, directed that the expense 

 of computing these tables for 1850 should be defrayed from the appro- 

 priation for the almanac — the printing and distribution to be done by the 

 Smithsonian Institution. A similar order has been given by Mr. Graham, 

 the present Secretary of the Navy, relative to the tables for 1851. 



Copies of these elements will be forwarded to all persons disposed to 

 advance the science of geography, with the request, that the results of the 

 observations which may be made, be sent to the Smithsonian Institution, or 

 published in some accessible scientific journal. 



The following remarks by the computer will give a more definite idea 

 of the nature and object of this publication. 



JOSEPH HENKY, Secretary S. I. 



CHARLES H. DAVIS, Superintendent of the Nautical Almanac. 



In preparing the following lists, I have endeavoured to afford to con- 

 ductors of the exploring operations which will, doubtless, be prosecuted by 

 our government in the newly acquired and other extensive territories of the 

 •West, every facility for the determination of the longitude of important 

 points. "With this view, I have included in the first or general list all the 



