A Popular History of Astronomy During the Nineteenth Century Fourth Edition
CHAPTER VI
THE SUN'S DISTANCE
Difficulty of the Problem--Oppositions of Mars--Transits of Venus--Lunar Disturbance--Velocity of Light--Transit of 1874--Inconclusive Result--Opposition of Mars in 1877--Measurements of Minor Planets--Transit of 1882--Newcomb's Determination of the Velocity of Light--Combined Result 227