ASTRONOMY — HAI^E. 65 



organized last summer at Oxford. A plan of cooperation in work with the 

 spectroheliograph has been perfected, involving the use of instruments in 

 India, Sicily, Germany, France, Spain, England, Mexico, and the United 

 States. The wide distribution of these spectroheliographs in longitude 

 will permit the sun to be kept almost constantly under observation, so 

 that the record of the state of the calcium flocculi will be sufficiently con- 

 tinuous for most purposes. The location of the Solar Observatory, be- 

 cause of its atmospheric advantages and its western longitude, and also 

 because of its powerful instrumental equipment, should enable it to con- 

 tribute in an important way to this international undertaking. The 

 Observatory will also be able to assist in the observation of sun-spot 

 spectra, and probably in other particulars. 



The acceptance by the late Secretary Langley of an invitation to con- 

 tinue on Mount Wilson the work inaugurated by the Smithsonian Institu- 

 tion in the spring of 1905 has resulted most successfully. The coopera- 

 tion we have thus been able to promote is proving advantageous to both 

 the institutions concerned, especially on account of the close relationship 

 between the Smithsonian studies of the solar constant and our own 

 investigations of other solar phenomena. The investigations of Prof. 

 E. F. Nichols on Mount Wilson, and the coming visit of Mr. John Ever- 

 shed, lately appointed assistant director of the Kodiakanal Solar Observa- 

 tory in India, afiford other instances of work which the Solar Observatory 

 hopes to continue and extend in the future. At this point I also wish to 

 speak of the visit of Messrs. Smith and McGrath, of the United States 

 Coast and Geodetic Survey, which is described more fully below. We 

 are heartily indebted to Superintendent Tittmann and the gentlemen 

 named for their cooperation in determining the astronomical latitude and 

 longitude of the Solar Observatory. 



STAFF. 

 At the opening of the year, Messrs. W. S. Adams and F. Ellerman were 

 engaged in observational work with the Snow telescope. In February 

 Dr. Henry G. Gale arrived from the University of Chicago, where he held 

 the position of Instructor in Physics at the Ryerson Physical Laboratory. 

 Dr. Gale was placed in charge of the work of our spectroscopic labora- 

 tory, in which he has recently been assisted by Dr. Charles M. Olmsted, 

 who joined the Observatory stafif, on temporary appointment, in August. 

 Mr. Francis G. Pease has also assisted in some of the experimental work 

 with the electric furnace in the Pasadena laboratory. Dr. H. K. Palmer, 

 of the Lick Observatory, joined our staff in May, and has been engaged in 

 bolographic investigations with the Snow telescope. He has also assisted 

 Mr. Ellerman in the routine work with the spectroheliograph. On July i 

 Mr. Adams left Mount Wilson to take charge of the computing division 



