After leaving school he worked on the farm, but, finding this labor uncongenial, he emigrated to New York in 1794, secured employment as a clerk or book-keeper, and speedily acquired a high reputation for industry and trustworthiness.

He married early in life, and occupied for a quarter of a century a house in Pearl Street.

In 1837 he removed to 17 Vandewater Street, where he resided until his death, and there found leisure for gratifying his taste for antiquarian research.

In a room at his house his valuable and unique collection of pictures, books, autographs, and rare and curious articles, especially attractive to the antiquary and virtuoso, was frequently viewed by visitors to the city and by others.

Allan's collection was sold at auction a short time after his death, and the total receipts amounted to $87,689.26.