90 POPULAR SCIENCE MONTHLY. 



tifically Professor Keeler never groped aimlessly in the dark. He would 

 not attack a problem until he had as fully as possible comprehended its 

 nature and the requirements for success. With the plan of attack com- 

 pletely considered, and the instruments of attack at hand, the execution 

 of his plans involved little loss of time. The Crossley reflector affords 

 a case in point. Assisted by a fellow in astronomy and by the instru- 

 ment-maker, he devoted five months to preparing the reflector for turn- 

 ing out the magnificent results which at once followed. 



Professor Keeler's published papers have a finish and a ripeness 

 which are rarely seen. His love of the beautiful and his artistic skill 

 are evident in all his work. 



To speak of the people who had afforded him encouragement at dif- 

 ferent times in his life was one of his pleasures. His father's friend, 

 Mr. Chas. H. Rockwell, of Tarrytown, was constant in urging the de- 

 velopment of so promising a career. He did not forget Professor Hast- 

 ings' continual kindness and interest during his college days. He fre- 

 quently spoke of the great value of Mr. William Thaw's interest and 

 encouragement, both to himself and to the Allegheny Observatory; an 

 interest which was continued after Mr. Thaw's death by other members 

 of his family. 



The honorary degree of Sc. D. was conferred upon Professor Keeler 

 in 1893 by the University of California. He received the Rumford 

 Medal from the American Academy of Arts and Sciences in 1898 and 

 the Henry Draper Medal from the National Academy of Sciences in 

 1899. He was a member of the National Academy of Sciences, an 

 Associate of the American Academy of Arts and Sciences, a Fellow and 

 Foreign Associate of the Royal Astronomical Society, a Fellow of the 

 American Association for the Advancement of Science, a member and 

 officer of the Astronomical and Astrophysical Society of America, an 

 honorary member of the Toronto Astronomical and Physical Society, 

 the president of the Astronomical Society of the Pacific, a member of 

 the Washington Academy of Sciences, and of various other organiza- 

 tions. Professor Keeler was an associate editor of 'Astronomy and As- 

 tro-physics' during 1892-94, and editor with Prof. George E. Hale of 

 'The Astrophysical Journal,' since 1895. 



It appears that Professor Keeler had long been a mild sufferer from 

 heart weakness; to run even fifteen steps caused him great physical dis- 

 tress. It is feared that on Mt. Hamilton he worked beyond his strength. 

 His weakness seemed to develop rapidly this summer. He went away 

 from the observatory on July 30, in the best of spirits and with no 

 anxiety, to secure medical treatment and to spend a brief vacation in the 

 northern part of the State. Increasing difficulty in breathing led him 

 to seek skilled treatment in San Francisco on August 10. His dangerous 



