My chief reason for confining these four talks to the outdoor sketch is because I have been an outdoor painter since I was sixteen years of age; have never in my whole life painted what is known as a studio picture evolved from memory or from my inner consciousness, or from any one of my outdoor sketches. My pictures are begun and finished often at one sitting, never more than three sittings; and a white umbrella and a three-legged stool are the sum of my studio appointments.