xxii GENERAL SUMMARY OF SCIENTIFIC AND 



rately determined by observations of an asteroid on each side 

 of the meridian, and Lord Lindsay announces that he will de- 

 vote his spare time at the island of Mauritius to such obser- 

 vations on the planet Juno. 



Among: the numerous investigations that have been insti- 

 tuted in connection with the preparations for the transit, is 

 one by Bakhuysen, of Leyden, who maintains that the phe- 

 nomenon of the black drop is mostly due to diffraction, and 

 lias its origin within the telescope. The papers prepared by 

 or for members of the French Commission have been collect- 

 ed in a single and very convenient volume. 



Dr. Vogel urges upon the observers of the approaching 

 transit of Venus special attention to the question of the ex- 

 istence of a satellite to that planet, as it may perchance ap- 

 pear on the disk of the sun. 



There will be a total eclipse of the sun shortly after the 

 transit of Venus, to observe which Janssen proposes to leave 

 his transit station at Yokohama and proceed to Siam. 



Observatories. The first in importance in America, and 

 we hope eventually in the world, will probably be that en- 

 dowed by Mr. James Lick, of San Francisco, in a fund amount- 

 ing to eight hundred thousand dollars in gold, set aside by 

 this gentleman for constructing an observatory in the most 

 suitable spot within the State of California. The adminis- 

 tration of this fund is in the hands of trustees chosen by 

 himself, and it is understood that they contemplate the erec- 

 tion of a refracting telescope of the largest attainable size, 

 though possibly the risks of such an experiment may justify 

 them in provisionally mounting a smaller glass at some ele- 

 vated station. 



The 26-inch refractor ordered some years ago by Mr. M'Cor- 

 mick, of Chicago, from Messrs. Alvan Clark & Sons, is an- 

 nounced to be nearly completed, and awaiting the orders of 

 its purchaser. 



The 28-inch mirror of Dr. Henry Draper, at Hastings, is, 

 we understand, being devoted to celestial photography, and 

 that with such success that "admirable photographs of the 

 spectra of stars" are obtained. 



The use of the Dudley Observatory, at Albany, has been 

 temporarily transferred to the Army Signal Office, until the 

 appointment of its new director, in which step the trustees 



