We frequently find, on some of our best land, large boulders, very hard, and too large to be removed, with any team we can command, and which would be in the way, in any place to which we might remove them. The best way to get rid of them, when it can be afforded, is to burn or blast them into pieces small enough to be easily handled. When this can not be afforded, the best method is to make an excavation by the side of them, deep enough to let them sink below the reach of the plow, and allow them to fall in, being careful not to get caught by them. ROLLER. This is quite as indispensable to good farming and gardening as any other tool. It serves a great variety of useful purposes. The first is to pulverize soils. No man can get a full crop on a soil not made fine on the surface, however rich that soil may be. It is often the case that land needs rolling two or three times before the last harrowing and sowing the seed. Another purpose is, on all light soils, to place the soil close around the seeds after they have been covered. When this is not done, seeds will vegetate very unevenly, and, in dry weather, some of them not at all. Another advantage of rolling a field-crop is the greater facility and economy with which it can be harvested. It makes a level, smooth surface, sinking small stones out of the way of the scythe or reaper. Rolling makes grass-seed catch, when sown with a spring-crop. All beds of small seeds--as onions, beets, carrots, parsnips, &c.--should be rolled after planting. It will so smooth the surface, that hoeing and cultivating can be done without injury to the plants. The rows are also much more easily seen while the plants are young. Any crop will grow better and larger by not being too much exposed to the action of the atmosphere on its roots. When the soil is coarse, part of the seeds and roots are greatly exposed to the action of the atmosphere, and this exposure is very irregular. The roller so crushes the lumps and fills up the openings in the soil as to cause the atmosphere to act regularly on the whole crop. Few farmers stop to think that the pressure of the atmosphere on their soils is fifteen pounds' weight on every square inch, and that, hence, the air must penetrate to a considerable depth into the soil; and where the soil is coarse, the air enters too freely, and acts too powerfully for the good of the plants. Rollers are made of wood, iron, or freestone. For most purposes, wood is best. A log made true and even, or, better, narrow plank nailed on cylindrical ends, are the usual forms. From eighteen inches to three feet in diameter is the better size. Iron or stone rollers, in sections, are best for pulverizing soil disposed to cake from being annually overflowed with water, or from other causes. ROOT CROPS.