MEMOIR OF SIMON NEWCOMB 
351 
published shortly after. In 1S99, Professor Newcomb completed his work 
on the six major planets he had undertaken to revise by the publication of 
tables of Uranus and Neptune. 
While all these investigations in the planetary theories were going on, 
Professor Newcomb must have found time for attacking his subject of 
predilection, the lunar theory, for we have a lengthy memoir by him on the 
action of the planets on the moon, contained in the volume last mentioned. 
This paper must have cost him an enormous amount of labor; he seems to 
be determined that no inequality of sensible magnitude should escape him. 
The tables of the planets being out of the way, Professor Newcomb next 
turned his attention to the fixed stars. Being present at the Paris Confer¬ 
ence of 1896 on a common international catalogue of fundamental stars, he 
obtained the assignment of the subject of precession as his share of the work 
to be undertaken. Within a year he had the work done, having derived a 
value of the principal constant involved which is probably as good as the 
condition of the data at the time allowed. 
This memoir is naturally followed by another containing a catalogue of 
more than 1,500 stars reduced to an absolute system and to be employed as 
fundamental. 
In March, 1897, Professor Newcomb, having arrived at the age limit, 
was retired from the office of the American Ephemeris. Many of his un¬ 
finished jobs were carried to completion under the nominal superintendence 
of others. 
At the foundation of the Carnegie Institution of Washington, Professor 
Newcomb secured the privilege of prosecuting his researches on the motion 
of the moon under its auspices. Here, until the end of his life, he labored 
assisted by a small but very able corps of assistants. Although the period 
of time was short, a long memoir on the planetary inequalities has appeared. 
The last contribution of Professor Newcomb to science is an article in the 
Monthly Notices for January, 1909, exhibiting the deviations of the moon’s 
mean longitude from the best theory that, so far, has been devised. 
In the intervals of leisure between his labors of a more technical kind, 
Professor Newcomb composed a book on “Popular Astronomy.” Al¬ 
though the rapid advance of the science in the more than thirty years since 
its publication has caused it to fall behind, it still remains the best composi¬ 
tion on the subject. 
Professor Newcomb contributed a vast number of notes on almost every 
conceivable topic in astronomy and the allied sciences to the scientific 
periodicals. (In this connection it may be useful to state that the Royal 
Society of Canada has published a bibliography.) He had the management 
of the construction of tables for the Watson asteroids. He found time to 
