138 
UPDEGRAFF. 
But he continued to devote his spare time to celestial me- 
chanics, and later was for some years on special duty mak- 
ing investigations of the motion of the moon. In 1877, 
after twenty years of broad and active experience in theo- 
retical and practical astronomy, he was made Superintendent 
of the Nautical Almanac Office, which in the meantime had 
removed from Cambridge to Washington. Thus were 
brought together the work to be done, the facilities and re- 
sources for doing it, and the man of all men to direct it. 
At that time practical or observational astronomy had out- 
run the accuracy of the theories for predicting the motions of 
the heavenly bodies. The tables of the sun, moon and 
planets, and the fundamental constants of astronomy were in 
a chaotic condition. While sufficiently accurate for the needs 
of navigators and the ordinary land surveyor, the accuracy 
of the theoretical astronomy of the day was totally inadequate 
for the requirements of exact science. 
As Superintendent of the Nautical Almanac Office, Profes- 
sor Newcomb proceeded without delay to deal with this situa- 
tion. He immediately made such improvements in the 
yearly volumes of the American Ephemeris and Nautical 
Almanac as were then practicable, secured modest but neces- 
sary increases in the appropriations for the work of the Office, 
and pushed with great vigor the work of “improving the 
tables of planets, moon and stars,” as was and still is required 
by the law. He established a series of publications entitled 
“Astronomical Papers of the American Ephemeris,” of which 
the first number, being a series of tables of eclipses, was pub- 
lished in 1879. Eight quarto volumes of these papers were 
published under the supervision of Professor Newcomb, and 
they contain tables of the sun and of all the planets and 
numerous researches in celestial mechanics and the funda- 
mental constants of astronomy. In his preface to the first 
volume of the Astronomical Papers, published in 1882, Pro- 
fessor Newcomb says, page X, “On assuming the superin- 
tendence of the American Ephemeris in 1877, the writer 
determined to employ the resources at his disposal to carry 
out, or at least to enter upon, a long cherished plan of execut- 
ing the work in question,” more or less as outlined above. 
