The next thing considered was the yoke for the buffalo; and while Frank sketched the plough, Fred made a drawing of the yoke, which was a single piece of wood made to fit the animal's neck, and bring the draught to the middle of the shoulder. It was held in place by a short rope passing under the neck, and the traces were fastened to the ends of the wood. "A plough, yoke, and traces, for a single buffalo, ought not to cost more than a dollar," Fred remarked; and the Doctor quite agreed with him. The further observation was made that when two or more buffaloes were used, they were harnessed "tandem," and not side by side as with oxen in most parts of the world. [Illustration: NATIVE WOODEN PLOUGH AND YOKE FOR OXEN.] A stronger and heavier plough was shown to our friends, and Mr. Segovia explained that it was intended for oxen instead of buffaloes, and was used for stirring the ground where the lighter plough was insufficient. Frank observed that the yoke was not supplied with bows, after the American plan, but had a couple of upright pins at each end to enclose the neck of the ox. When the team is to be made up, the yoke is held over the necks of the animals, and dropped into place; and if they are at all restive, the space at the lower ends of the pins is closed by means of a cord. A rope, instead of a chain, forms the connection between the yoke and the beam of the plough. The latter has only one handle, on the theory that the ploughman needs the use of one of his hands for guiding his team, and consequently a double hold on the plough is impossible. [Illustration: THE COMB HARROW.] From the ploughing-ground they passed a little farther on to where a stretch of muddy ground was being harrowed, so as to make it ready for planting rice. Two or three inches of water covered the ground, and the object of the harrowing was to convert the water and earth into a bed of liquid mud. For this purpose a novel kind of implement was used; it was called a comb harrow, and had a single row of iron teeth fixed in a wooden frame. The traces of the buffalo were fastened so that they had a tendency to draw the teeth forward, and the machine was steadied by a handle or cross-bar parallel to the beam in which the teeth were placed. It was a simple and very effective instrument, and Frank thought it might be used to advantage on certain parts of his father's farm in America.