binaries, 132, 135;
new, 19, 36, 137;
catalogues of, 19, 36, 139;
spectra of, 143
Stewart, B., 2, 100
Stokes, G. G., 91
Stone, E. J., 139
Struve, C. L., 130
Struve, F. G. W,, 88, 115, 128, 133

Telescopes invented, 47, 86;
large, 88
Temple, 115, 125
Thales, 13, 16
Theon, 60
Transit circle of Romer, 78
Timocharis, 17, 19
Titius, 66
Torricelli, 113
Troughton, E., 80
Tupman, G. L., 120
Tuttle, 125
Tycho Brahe, 23, 25, 30, 33-38, 39, 40, 44, 50, 75, 77, 93, 94, 129, 137

Ulugh Begh, 24
Uranus, discovery of, 65

Velocity of light, 86, 128;
of earth in orbit, 128
Verbiest, 75