In 1808, Turner was appointed professor of perspective in the Royal Academy, which position he held for thirty years, though he rarely gave lectures to students, owing to his confused manner and obscurity in the use of language. Ruskin says: "The zealous care with which Turner endeavored to do his duty is proved by a large existing series of drawings, exquisitely tinted, and often completely colored, all by his own hand, of the most difficult perspective subjects; illustrating not only directions of line, but effects of light, with a care and completion which would put the work of any ordinary teacher to utter shame. In teaching generally, he would neither waste time nor spare it; he would look over a student's drawing at the Academy, point to a defective part, make a scratch on the paper at the side, say nothing. If the student saw what was wanted, and did it, Turner was delighted; but if the student could not follow, Turner left him." Turner this year moved to the Upper Mall, Hammersmith, where his garden extended to the Thames. In this he had a summer-house, where some of his best work was done. He still retained the Harley-Street house, and lived in it much the life of a recluse. Mr. Thornbury tells the following incident:-- "Two ladies called upon Turner while he lived in Harley Street. On sending in their names, after having ascertained that he was at home, they were politely requested to walk in, and were shown into a large sitting-room without a fire. This was in the depth of winter; and lying about in various places were several cats without tails. In a short time our talented friend made his appearance, asking the ladies if they felt cold. The youngest replied in the negative; her companion, more curious, wished she had stated otherwise, as she hoped they might have been shown into his sanctum or studio. After a little conversation he offered them wine and biscuits, which they partook of for the novelty, such an event being almost unprecedented in his house. One of the ladies bestowing some notice upon the cats, he was induced to remark that he had seven, and that they came from the Isle of Man." Turner was fond of his pet cats, and would let no harm come to them. After he had moved, in 1812, to 47 Queen-Anne Street, one of his favorite pictures, "Bligh Shore" was used as a covering for a window. A cat desiring to enter the window scratched the picture severely, and was about to be punished for the offence, by Mrs. Danby, the housekeeper, when Turner said, "Never mind," and saved the cat from the whipping.