In the first half of the eighteenth century the romance of the middle ages, though dying, was not dead, and the occult sciences still found followers among the Oxford towers. From his early years Temple's mind seems to have been set strongly towards mysticism of all kinds, and he and Jocelyn were versed in the jargon of the alchemist and astrologer, and practised according to the ancient rules. It was his reputation as a necromancer, and the stories current of illicit rites performed in the garden-rooms at St. John's, that contributed largely to his being dismissed from that College. He had also become acquainted with Francis Dashwood, the notorious Lord le Despencer, and many a winter's night saw him riding through the misty Thames meadows to the door of the sham Franciscan abbey. In his diaries were more notices than one of the "Franciscans" and the nameless orgies of Medmenham.
He was devoted to music. It was a rare enough accomplishment then, and a rarer thing still to find a wealthy landowner performing on the violin. Yet so he did, though he kept his passion very much to himself, as fiddling was thought lightly of in those days. His musical skill was altogether exceptional, and he was the first possessor of the Stradivarius violin which afterwards fell so unfortunately into Sir John's hands. This violin Temple bought in the autumn of 1738, on the occasion of a first visit to Italy. In that year died the nonagenarian Antonius Stradivarius, the greatest violin-maker the world has ever seen. After Stradivarius's death the stock of fiddles in his shop was sold by auction. Temple happened to be travelling in Cremona at the time with a tutor, and at the auction he bought that very instrument which we afterwards had cause to know so well. A note in his diary gave its cost at four louis, and said that a curious history attached to it. Though it was of his golden period, and probably the finest instrument he ever made, Stradivarius would never sell it, and it had hung for more than thirty years in his shop. It was said that from some whim as he lay dying he had given orders that it should be burnt; but if that were so, the instructions were neglected, and after his death it came under the hammer. Adrian Temple from the first recognised the great value of the instrument. His notes show that he only used it on certain special occasions, and it was no doubt for its better protection that he devised the hidden cupboard where Sir John eventually found it.