A Light Sand.--This is a soil containing ninety per cent of sand. If it had more sand and less of clay and other matter it would hardly produce any useful plants, and could not fairly be called a soil. 2. A Pure Clay.--This would be a soil in which no sand could be found. A pure clay soil would be wet and cold, and would not be good for our common plants. Such soils are rare: and what is commonly called a pure clay soil is one containing a great excess of clay, and only a little sand or other matter. 3. A Loam.--This is one of the best of all soils. Such a soil contains both sand and clay as well as other matter. 4. A Sandy Loam.--This is a mixture of sand and clay, with more sand than clay. 5. A Clay Loam.--This is a mixture in which there is more clay than sand. 6. A Strong Clay.--This is a clay containing from five to twenty per cent of sand and other matter. Experiments with Sand and Clay.--Procure a quart of pure sand and spread it out in the sun to dry, and when dry place a small quantity on a spoon, and hold over a hot fire. The heat has no effect upon it. Remove the spoonful of sand from the fire, and it will be found that the sand keeps its heat for a long time. Place a small quantity of sand in a small sieve and pour water over it. The water at first flows away more or less discolored, and presently runs quickly through the sand pure and clean. While wet the sand sticks together slightly. Place it in the air, and it soon dries, and the grains are as loose as before. Place a little of the washed sand in a bottle filled with water. Cork the bottle and shake it up. The sand will move about as long as the water is in motion, but the instant the bottle is at rest, it falls to the bottom, and forms a layer under the clear water. Place some of the sand in an oven or in the sun till perfectly dry. Place three tablespoonfuls of water in a saucer, and then pour carefully into the saucer a cupful of dry sand. It becomes wet around the little heap while still dry at the top; soon the water will begin to creep up the sand and in a short time it is all wet, and remains wet as long as there is water in the saucer. These experiments show us that sand is not affected by heat, and that it keeps its heat for some time; that water passes through it readily and, if clean, the water passes through pure and clean. When wet it is very slightly sticky, when dry this stickiness disappears completely. In water it sinks the moment the water is at rest. Water rises through it easily by capillary attraction. Another experiment, taking more time, is to place some clean sand in a flower pot, wet it, and sprinkle fine grass-seeds over it. Place in a warm room and the seeds will soon sprout and send small roots down into the sand.