EuroGraphics Study for Northern River by Tom Thomson 1000-Piece Puzzle. Box size: 10" x 14" x 2.37". Finished Puzzle Size: 19.25" x 26.5". Tom Thomson was largely self taught and did not seriously pursue becoming a painter until he was in his thirties. He was one of the Group of Seven, a well known group of Canadian artists from the early twentieth century. With Study of Northern River, Thomson shows his ability to transform a sketch into a successful studio painting. Strong high-quality puzzle pieces. Made from recycled board and printed with vegetable based ink. This superior quality puzzle will delight and educate all at the same time.