The planting of great fields of potatoes has been greatly facilitated by machinery that first slices them and then sows the slices continuously in a row, or drops them in separate spots or hills, as may be desired. The finest seeds, such as grass and clover, onion and turnip seed, and delicate seed like rice, are handled and sown by machines without crushing or bruising, and with the utmost exactness. Just what seed is necessary to be supplied to the machine for a given area is decided upon, and the machine distributes the same with the same nicety that a doctor distributes the proper dose of pellets upon the palm of his patient. Transplanters as well as planters have been devised. These transplanters will dig the plant trench, distribute the fertiliser, set the plant, pack the earth and water the plant, automatically. The class of machines known as cultivators are those only, properly speaking, which are employed to cultivate the plant after the crop is above the ground. The duties which they perform are to loosen the earth, destroy the weeds, and throw the loosened earth around the growing plant. Here again the laborious hoe has been succeeded by the labour-saving machine. Cultivators have names which indicate their construction and the crop with which they are adapted to be used. Thus there are “corn cultivators,” “cotton cultivators,” “sugar-cane cultivators,” etc. Riding cultivators are known as “sulky cultivators” where they are provided with two wheels and a seat for the driver. If worked between two rows they are termed single, and when between three rows, double cultivators. A riding cultivator adapted to work three rows has an arched axle to pass over the rows of the growing plants and cultivate both sides of the plants in each row. Double cultivators are constructed so that their outside teeth may be adjusted in and out from the centre of the machine to meet the width of the rows between which they operate. A “walking cultivator” is when the operator walks and guides the machine with the hands as with ploughs. Ordinary ploughs are converted into cultivators by supplying them with double adjustable mould boards. Ingenious arrangements generally exist for widening or narrowing the cultivator and for throwing the soil from the centre of the furrow to opposite sides and against the plant. The depth to which the shares or cultivator blades work in the ground may be adjusted by a gauge wheel upon the draught beam, or a roller on the back of the frame. Disk cultivators are those in which disk blades instead of ploughs are used with which to disturb the soil already broken. As with ploughs, so with cultivators, steam-engines are employed to draw a gang of cultivating teeth or blades, their framework, and the operator seated thereon, to and fro across the field between two or more rows, turning and running the machine at the end of the rows.