[2] In 1878, his parents moved to Oakland where his father, a retired medical practitioner, opened a pharmacy.

Henry attended the University of California, Berkeley, while assisting his father to earn his school fees, graduating with a B.Phil.

[4][5] While a student, he was elected and served as the Justice of the Peace of Brooklyn Township in Alameda County.

[12][8] In 1904, the Legislature approved creation of the Courts of Appeal and Melvin was considered for one of the seats in the Second District but not chosen by Governor George Pardee.

[13] In September 1908, Melvin was nominated by the Republican Party and appointed by Governor James Gillett as an associate justice of the Supreme Court of California.