William Earl Hidden was the son of James Edward, and Abbie Angel Hidden, and was born in Providence, R. I., February 16, 1853. He died, from heart trouble, in Newark, N. J., on June 12, 1918, being thus in his sixty-sixth year at the time of his death. He received his education in the public schools of Providence, New York, and Washington. In 1873–1877 he attended the chemical lectures of Prof. Charles F. Stone; and he joined the New York Academy of Sciences in 1875. For some time he was employed as draughtsman by the American Bank Note Company, and was unusually successful in this art, but his interest in minerals, stamps, coins, etc., weaned him from it, and he finally abandoned it in 1884.