The future architect of St. Paul’s had already been called upon to devote a portion of his time to the professional exercise of that art from which he was destined to derive his greatest and most lasting distinction. Sir John Denham, the poet, had on the Restoration been rewarded for his services by the place of Surveyor of the Royal Works; but although, in his own words, he then gave over poetical lines, and made it his business to draw such others as might be more serviceable to his Majesty, and he hoped more lasting, it soon became apparent that his genius was much better suited to “build the lofty rhyme” than to construct more substantial edifices. In these circumstances Wren, who was known among his other accomplishments to be well acquainted with the principles of architecture, was sent for, and engaged to do the duties of the office in the capacity of Denham’s assistant or deputy. This was in the year 1661. It does not appear that for some time he was employed in any work of consequence in his new character; and in 1663 it was proposed to send him out to Africa, to superintend the construction of a new harbour and fortifications at the town of Tangier, which had been recently made over by Portugal to the English Crown, on the marriage of Charles with the Infanta Catherine. This employment he wisely declined, alleging the injury he apprehended to his health from a residence in Africa. Meanwhile, the situation which he held, and his scientific reputation, began to bring him something to do at home. Sheldon, Archbishop of Canterbury, who was Chancellor of the University of Oxford, had resolved to erect at his own expense a new theatre, or hall, for the public meetings of the University; and this building Wren was commissioned to design. The Sheldonian Theatre, celebrated for its unrivalled roof of eighty feet in length by seventy in breadth, supported without either arch or pillar, was Wren’s first public work, having been begun this year, although it was not finished till 1668. About the same time he was employed to erect a new chapel for Pembroke College, in the University of Cambridge, to be built at the charge of his uncle, the Bishop of Ely.