both in his scientific discoveries and in his personal traits. He was not a mathematician, he was not always familiar with work that had been done in the same direction as his own, he did not have assistants nor use the ordinary machinery of research. But he had ideas, which he worked out with originality and persistence, devising his own methods and making his own instruments.
Rood was born in Connecticut on February 3, 1831, his father being a clergyman. He was dismissed from Yale College for some student escapade it is said because he stopped chapel by shooting an arrow into the face of the college clock and it was with some satisfaction that he received the doctorate of laws from Yale University on the occasion of its bicentennial.
He graduated at Princeton in 1852, and spent several years in study abroad, a course not common in the fifties. For five years he was professor in a small denominational institution at Troy. Then at the early age of thirty-three he was called to Columbia College and at