My preparation for college was partly under the private tutorship of the good old Dutch dominie, the Rev. Gerrit Mandeville, who smoked his pipe tranquilly while I recited to him my lessons in Caesar's Commentaries, and Virgil; and partly in the well-known Hill Top School, at Mendham, N.J. I entered Princeton college at the age of sixteen and graduated at nineteen, for in those days the curriculum in our schools and universities was more brief than at present. The Princeton college to which I came was rather a primitive institution in comparison with the splendid structures that now crown the University heights. There were only seven or eight plain buildings surrounding the campus, the two society-halls being the only ones that boasted architectural beauty. In endowments the college was as poor as a church mouse. There were no college clubs, no inter-collegiate games, thronged by thousands of people from all over the land; but the period of my connection with the college was really a golden period in its history. Never were its chairs held by more distinguished occupants. The president of the college was Dr. Carnahan, who, although without a spark of genius, was yet a man of huge common sense, kindness of heart and excellent executive ability. In the chair of the vice-president sat dear old "Uncle Johnny" McLean, the best-loved man that ever trod the streets of Princeton. He was the policeman of the faculty, and his astuteness in detecting the pranks of the students was only equalled by his anxiety to befriend them after they were detected. The polished culture of Dr. James W. Alexander then adorned the Chair of the Latin Language and English Literature. Dr. John Torrey held the chemical professorship. He was engaged with Dr. Gray in preparing the history of American Flora. Stephen Alexander's modest eye had watched Orion and the Seven Stars through the telescope of the astronomer; the flashing wit and silvery voice of Albert B. Dod, then in his splendid prime, threw a magnetic charm over the higher mathematics. And in that old laboratory, with negro "Sam" as his assistant, reigned Joseph Henry, the acknowledged king of American scientists. When, soon after, he gave me a note of Introduction to Sir Michael Faraday, Faraday said to me: "By far the greatest man of science your country has produced since Benjamin Franklin is Professor Henry." With Professor Henry I formed a very intimate friendship, and after he became the head of the Smithsonian Institution I found a home with him whenever I went to Washington.