A turning sun for use on water is formed from two jets joined together by their ligatures. The pair is fastened on a pine board, cut round, of a diameter equal to the length of a jet, and sufficiently thick to sustain the two jets on the water. A lateral hole is made with a gimlet at the end of one of the jets to the right, and another hole at the opposite end of the other jet to the left. A match inclosed in a lance case, which extends from one hole to the other, communicates its fire to both at the same time. The movement of rotation is produced by the holes so pierced as to oppose each other. The fire, issuing thus, impresses on them two opposed movements by which the piece is forced to turn, and the middle of the length becomes the center of this movement. (PL. X, fig. 10.)