Maech 24, 1911J 



SCIENCE 



447 



pletely destroyed, along with a consider- 

 able number of books and other valuable 

 property, by fire. This building has been 

 replaced during the year in somewhat en- 

 larged form by a reinforced concrete 

 structure. 



Progress has been made during the year 

 in the details of designs for the proposed 

 100-ineh or "Hooker" telescope, for which 

 Mr. J. D. Hooker, of Los Angeles, made a 

 substantial gift to the observatory some 

 years ago. This work has been in charge 

 of Professor Ritehey, whose construction 

 of the 60-inch reflector has proved so 

 signally successful. After repeated trials 

 and failures to make a satisfactory disk the 

 contracting firm at St. Gobain, Prance, 

 have quite recently renewed the hope that 

 a disk they now have annealing may meet 

 the exacting requirements set by the as- 

 tronomers. 



Allusion has already been made in an 

 earlier part of this report to the meeting of 

 the International Union for Cooperation 

 in Solar Research held at the observatory 

 during the week of August 29 to Septem- 

 ber 4 of the current year. An outline of 

 the proceedings of this meeting, which was 

 of peculiar interest to the observatory 

 staff, is given by the acting director at the 

 end of his report. In spite of the difficul- 

 ties of access to the observatory site, this 

 meeting was regarded as the most impor- 

 tant held by the union. Opportunities 

 were afforded the visiting astronomers and 

 physicists to inspect the entire establish- 

 ment and to test especially the efficiency of 

 the telescopic apparatus. Their apprecia- 

 tion of these opportunities and of the 

 optical perfection of the telescopes, partic- 

 ularly of the 60-inch equatorial reflector, 

 is a source of keen encouragement to the 

 observatory staff. 



Attention is invited to the interosting 

 account given in the departmental report 



of the numerous investigations now under 

 way at the observatory and in the phys- 

 ical laboratory at Pasadena. They are so 

 effectively summarized in this report that 

 any restatement appears superfluous. 



No department of research in the insti- 

 tution is conducting work which is at once 

 so obviously practical and so obviously 

 theoretical as the work of the department 

 of terrestrial magnetism. Every one ac- 

 quainted with the daily use of the compass 

 in exploration, in surveying, and in navi- 

 gation recognizes the practical utility of a 

 magnetic survey of the earth. But those 

 who recognize that any utilitarian results 

 may come from a deeper knowledge of the 

 earth's magnetism and its cosmic connec- 

 tions are at present verj' limited in num- 

 ber. Nevertheless, the history of science 

 warrants a confident expectation that the 

 latter residts will ultimately prove to be of 

 much greater value than the former. 



The more striking events of the year in 

 this department refer naturally to the non- 

 magnetic ship Carnegie, which was off on 

 her first cruise at the close of the previous 

 fiscal year. She was then at Falmouth, 

 England, where her determinations of the 

 magnetic elements were compared with in- 

 dependent determinations made at the 

 permanent magnetic observatory of that 

 port. She proceeded thence, November 9, 

 1909, to Funehal, Madeira ; thence to Ham- 

 ilton, Bermuda; and thence, under tem- 

 pestuous conditions which proved her sea- 

 worthiness, to Brooklyn, N. T., where she 

 arrived February 17, 1910. Here she had 

 her copper sheathing applied by the con- 

 structors, as required by their contract, 

 and was overhauled and refitted for a three 

 years' circumnavigation cruise. It is a 

 pleasant duty to report that in all essen- 

 tial respects this vessel has proved more 

 effective than was anticipated. It has been 

 demonstrated that even in rough weather 



