tangent, 51 Tannery, 43 teaching, 430, 437 thermodynamics, 115, 119 Thomson, 98, 488 thread, 104 time, 223 equality, 225 local, 306, 307 measure of, 223-4 Tisserand, 515-6 Tolstoi, 354, 362, 368 Tommasina, 519 Transylvania, 203 triangle, 58 angle sum of, 58 truth, 205 Tycho Brahe, 133, 153, 228 unity of nature, 130 universal invariant, 333 Uriel, 203 van der Waals, 153 Vauban, 210 Veblen, 203 velocity of light, 232, 312 Venus of Milo, 201
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