THE SMITHSONIAN INSTITUTION. 221 



mens are of much scientific interest, showing, as they do, for the first 

 time, the existence in this country of an eocene deposite, rivaUng in 

 the number of its species of extinct animals the celebrated basin of 

 Paris. 



Occuhalwm. 



It has been mentioned in the preceding reports, that lists of occula- 

 tions, and tables of reductions, have been published, from 1848 to 1851, 

 inclusive. The cost of the computation of these tables, as well as that 

 of their publication for the past two years, was borne by the Institution, 

 but since then Congress has ordered the establishment of an American 

 Nautical Almanac ; and as these tables will form a part of this epheme- 

 ris, Mr. Preston, the late Secretary of the Navy, directed that the ex- 

 pense of the computation should be defrayed from the appiopriation 

 lor the Almanac, the printing and distribution to be at the charge of the 

 Institution. A similar order has been given by the Hon. Wm. A. 

 Graham, the present Secretary of the Nav}^, relative to the tables for 

 1851 and 1852. 



The tables for 1852 are much extended by the introduction of occul- 

 tations visible in ever}^ part of the earth. The form is also somewhat 

 altered, in order better to adapt it to the arrangement to be adopted by 

 the Nautical Almanac. 



The primary object of these tables is to facilitate the accurate deter- 

 mination of the longitude of places within the territory of the United 

 States ; and in this respect they Imvc done good service, especially in 

 the hands of the officers of the Coast Survey, and the explorers and sur- 

 veyors of our new possessions on the coast of the Pacific. Their exten- 

 sion will render them useful to geographers in every part of the world. 

 They have been computed, for the present and the last two years, under 

 the direction of Lieut. Davis, the accomplished superintendent of the 

 American Nautical Almanac. As soon as this work, which will be an 

 honor to the country, is ready to be issued, the publication will be re- 

 linquished by the Smithsonian Institution. 



We observe again, in this case, the policy of not expending the funds 

 of the Institution in doing what other means can accomplish. 



It will be recollected that Mr. Sears C Walker, astronomical assistant 

 of the United States Coast Survey, prepared for the Smithsonian Trans- 

 actions a memoir containing a determination of the true orbit of the 

 planet Neptune, and that from this orbit, and the mathematical investiga- 

 tions of Professor Peirce, an ephemeris of Neptune was compiled. The 

 ephemeris was prepared for the years 1848 and 1849, under the direc- 

 tion and at the expense of this Institution ; but for the years 1850, '51, 

 '52, it was computed under the superintendence of Lieutennat Davis, 

 and at the expense of the appropriation for the Nautical Almanac, 

 while the cost of printing and of the distribution has been defra3^ed by 

 the Institution. 



The ephemeris has been generally adopted by the principal astrono- 

 mers of the world ; and Professor Airy, the astronomer royal of Great 

 Britain, has undertaken the labor, in his last volume of Greenwich 

 Observations, of critically comparing his observations on the planet in 



