xx GENERAL SUMMARY OF SCIENTIFIC AND 



and general perturbations of the eight principal planets hav- 

 ing at length been brought to a conclusion, he has presented 

 an account of them to the French Academy of Sciences, and 

 announces that his tables of Saturn, Uranus, and Neptune 

 are rapidly approaching completion. 



The somewhat startling announcement recently made by 

 Mr. Stockwell, of Ohio, that he had discovered important 

 errors in the mathematical portions of the accepted lunar 

 theories, and which he has undertaken to correct, has, we be- 

 lieve, been negatived by the reply of Schjellerup, of Copen- 

 hagen, according to whom the error is apparently on Mr. 

 StockwelPs own side. 



Veltmann applies to the general law of movements of three 

 or more bodies the calculus of determinants, and in this way 

 arrives at some interesting formula?. 



ASTRONOMY. 



Observers, Observatories, and Instruments. The publica- 

 tion of the excellent series of astronomical engravings has 

 been concluded by the Observatory at Harvard College. 

 The text is also prepared, and will probably be published 

 immediately on the appointment of Professor Winlock's suc- 

 cessor. 



The observatory erected on the grounds of Columbia Col- 

 lege, in New York, has been connected with the systems of 

 telegraph lines throughout the city, and will, it is hoped, 

 soon be in a position to systematically furnish standard time 

 to that city. 



The great Cassegrainian reflector, of 2G inches' aperture, 

 constructed by Dr. Henry Draper, has been properly mount- 

 ed in a dome, with every convenience for use, at his father's 

 country-seat at Hastings-on-the-Hudson ; but its great pow- 

 ers have not, as yet, on account of bad weather, been fully 

 demonstrated. For the sake of astronomy in America, it is 

 to be hoped that he may be able to wrest from many business 

 cares some time for the prosecution of astronomical physics. 



In connection with the observations of the transit of Ve- 

 nus, it should be mentioned that the American parties owe a 

 great deal of their success in photographic matters to the 

 friendly counsel of Dr. Draper, who very generously devot- 

 ed two months' time to the proper outfit of the parties in 



