SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 105 



in the lomg luttar day. Also that deep cracks or ravines — lat first almost 

 black— changed to a grayigh 'tint and broadened out to a measurable 

 extent. He accounts for tihie latter phenouieuon by assuming that 'there 

 is a little moisture beneath the surface in 'these localities, and that 

 the iheat of the sun melts tbe frozen crystals and instantly transforms 

 them into vapor which rises to the surface and fills the depressions, 

 broadening out to visibility. 



Eegarding the brown patches, he thinks there may be a low form 

 of vegetation capable of quick growthj and development, whidh would 

 account for the slight change in color perceived from the vantage site 

 of the Lowe Observatory, but also previously noticed at the Arequipa 

 Observatory in the high Andes, over which Prof. Pickering presided for 

 some years. Other astronomers have noted these lunar markings and 

 their verity is now conceded, but there is not a perfect agreement as 

 to their cause. 



Eeferring to the so-called canals of Mars, Prof. Pickering believes 

 they are caused by the same agency, but acting on a larger scale, and 

 on a body in which the atmosphere and vapor are not wholly absorbed 

 into the interior. He does not admit that there are any seas on the 

 surface of Mars. Btit the canal appearance is produced by vapor 

 being exuded from long, deep cracks and spread along the margin to 

 such an extent as to make the phenomenon visible under good-seeing 

 in our powerful telescopes. 



Prof. Pickering's lecture was preceded by Secretary Baumgardt's 

 account of an interesting gathering of astronomical workers on Mount 

 Wilson. Prof. Geoirge E. Hale, Director of the Yerkes Observatory; 

 Dr. Herbert H. Turner, Director of the Oxford University Observatory; 

 Prof. G. W. Eitchey, Optician of tbie Yerkes Observatory, and Prof. 

 Wm. H. Pickering of the Arequipa Observatory in South America were 

 among the distinguished astronomers Mr. Baumigardt met on that oc- 

 casion. They were on Mount Wilson inspecting the new instrument 

 now being installed by Prof. Hale for furtherinig reseaTches into the 

 constitution of the sun. This instrument is a coelostadt, and tiie tube, 

 five feet in diameter, is 145 feet in length, and imbedded in solid 

 granite. The tube is horizontal and fixed, a large plane, movable 

 mirroT Teflecting objects froim every portion of the tieavens into the tube 

 where the image is magnified to any desired degree. The summit of 

 Mount Wilson is 5886 feet above sea level and about thirty miles north- 

 east of Los Angeles. It was selected from among many other sites 

 examined as being the most suitable from which to conduct Prof. Hale's 

 asitrophysieal investigations of the sun. 



President Dozier announced that an arrangement has been effected 

 with the Trustees of the State Normal School which gives the use of 

 one of the halls to the Academy of Sciences for its general and section 

 meetings on each Monday evening during the season of lf'04-1905. 



WM. H. KNIGHT. 



II. MEETINGS OF SECTIONS. 



No meetings of Sections are held in June. The Board of Direc- 

 tors, by advice of the Chairmen, on account of the difficulty of getting 

 speakers and gathering audiences earlier than October, ipassed a resolu- 

 tion susrpending the meetings of aid Sections in September, also. Eegular 

 meetings will be resumed in October, at the State Normal School. 



