This gentleman was son of the Rev. John Dalton, rector of Dean, in Cumberland, where he was born in 1709. He was a member of Queen's College, Oxford, and took the degree of M.A. May 9, 1734. He afterwards became tutor or governor to the only son of Algernon Seymour, Duke of Somerset, a very hopeful and promising young gentleman, whose death in the bloom of youth and expectation stands on record in a very affecting manner in two letters on that occasion, written by his afflicted mother, the Countess of Hertford, afterwards Duchess of Somerset, and which since her death have been published in Mr. Duncombe's Collection of Letters. On the 4th of July, 1750, he was honoured with the degrees of B. and D.D. At the time of his death, which happened July 21, 1763, he was prebendary of Worcester, and rector of St. Mary-at-Hill. Dr. Dalton's claim to a mention in this work is his having altered, and rendered more fit for dramatic exhibition, Milton's admirable Masque at Ludlow Castle, which he considerably extended, not only by the insertion of several songs from other of Milton's works, but also by the addition of several songs and improvements of his own, so admirably adapted to the manner of the masque, as by no means to disgrace the more genuine parts, but, on the contrary, to exalt our ideas of Dr. Dalton's poetical abilities. It has, moreover, had the advantage of being most excellently set to music by Dr. Arne, and is sometimes acted under the title of Comus. Masque. 8vo. 1738.
During the run of Comus, he industriously sought out a grand-daughter of Milton (Elizabeth Foster), oppressed by age and poverty, and procured her a benefit from it at Drury Lane Theatre, on the 5th of April 1750, by which she cleared above £130. Mr. Garrick spoke a prologue, which was written by Dr. Johnson for the occasion.