ON THE PROGRESS OF SCIENCE. 23 



quired in physical investigations. These tables supply a desideratum in 

 the English language, and will doubtless be highly prized by all engaged in 

 physical research. It is proposed to extend their number so as to include 

 a wider range of objects, and to publish them in parts to suit different 

 purposes. 



" Researches on Electrical Rheometry," by Prof. Secchi; " Description 

 of Ancient Works in Ohio," by Charles Whittlesy; "On the Ancient 

 Works at Prescott, Canada West," by William E. Guest. The great size 

 of the remains of trees which occupy the ground, evince the long time 

 which must have elapsed since these works were constructed, and the 

 entire absence of stone pipes and arrow heads has induced the belief that 

 they are of a higher antiquity than those in the Ohio valley. 



List of occultations and tables of reductions have been published from 

 1848 to 1852, inclusive. The primary object of these tables is, to facilitate the 

 accurate determination of the longitude of places within the territory of 

 the United States; and in this respect they have done good service, espe- 

 cially in the hands of the officers of the coast survey, and the explorers 

 and surveyors of our new possessions on the coast of the Pacific. Their 

 extension will render them useful to geographers in every part of the 

 world. 



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

 of the United States coast survey, prepared for the Smithsonian Transac- 

 tions a memoir containing a determination of the true orbit of the planet 

 Neptune, and that from this orbit, and the mathematical investigations of 

 Professor Pierce, an ephemeris of Neptune was compiled. The epheme- 

 ris has been generally adopted by the principal astronomers of the world; 

 and Professor Airy, the astronomer royal of Great Britian, has undertaken 

 the labor, in his last volume of Greenwich Observations, of critically 

 comparing his observations on the planet in the heavens with the predic- 

 tions of the Smithsonian ephemeris. From these comparisons it is found 

 that the ephemeris gives the position of the planet with a degree of pre- 

 cision not interior to that with which the planets longest known are 

 calculated. The labors, therefore, of Mr. Walker on the elements, and 

 Professor Pierce on the theory of the planet Neptune, have been crowned 

 with complete success. It is proposed hereafter to collect all the observa- 

 tions which may have been made on the planet, and compare them with 

 the ephemeris, in order, if necessary, still further to correct the orbit. 



The general system of meteorology now in operation in this country un- 

 der the auspices of the Smithsonian Institution, is continually enlarging 

 and extending. The Institution has at the present time a corps of trained, 

 intelligent men, between two and three hundred in number, extended over 

 the entire continent, and making frequent observations, many with stand- 

 3* 



