Burning, the action of fire on fuel, the minute parts of which are thereby put into violent com-motion, so that some of these particles assume the nature of fire, and escape, while the remainder is either dissipated in the form of va-pour, or reduced to ashes. There are many instances on record, of persons who have been burnt to death by fires kindled in their own bodies : but such individuals generally had long indulged to excess in spirituous liquors.

Burning, in surgery, denotes the application of the actual cautery, or a red hot instalment, to the part affected. In the Mogul empire, the natives cure, or pretend to cure the colic, by applying a ring, red hot, to the patient's navel ; and among the Japanese, the practice of burning constitutes nearly the whole of the healing art. It is, however, certain, that several very extraordinary cures have been performed by burning: and the ancients frequently had recourse to this remedy, with singular advantage.

Burning-Glass, or burning mirror, a machine by which the sun's rays are collected into a point, and thus their force and effect considerably increased, so as to consume objects within its reach.

There are two kinds of burnin glasses, namely, convex and con-cave. Those of the convex form are lenses, which, by acting according to the laws of refraction, incline the rays of light towards the axis, and unite them in a point, or focus. The concave ones are mirrors, or reflectors, whether made of polished metal, or silvered glass ; which, by the laws of reflection, throw back the rays into a, point before the glass.

These instruments are undoubtedly of very ancient origin: the most celebrated were those of Archimedes and Proclus; by the former of which the fleet of Mar-cellus was destroyed, at the distance of a bow-shot. In modern times, there have been several inventions of this kind, remarkable for their large diameter, and powerful effects, - the principal of which; are those of MAGINE, of Sepatala, Settala, and Buffon ; the latter of whom made one that consisted of 400 mirrors, which reflected all their rays to one point, and with this he could melt lead and tin, at the distance of 140 feet.

Sir Isaac Newton presented a burning-glass to the Royal Society, which consisted of seven concave glasses, so placed that all their foci join in one physical point. This instrument virtifies brick or tile in one second, and melts gold in half a minute.

Burning of Land, or Burn-lairing, a practice lung employed in agriculture, but now nearly abandoned. It is performed by cutting off the turf of the ground, piling it in heaps to dry, and afterwards burning it to ashes, which are spread over the bare surface and ploughed in. Many consider it as a very profitable method of dressing, for it need only be used on the poorest, and worst kind of lands, or barren, rushy, and heathy grounds, that have long been un-tilled. By this useful practice, an excellent crop may be obtained from the most impoverished soil ; though the effect does not continue longer than three years, when the ground becomes as poor as it was before.

Land may be so much exhausted, by repeated crops after burn-baiting, as not to receive benefit from any thing, till recruited by ten or twelve years fallow : hence the farmer should, after the first crop, prepare for the second, by the addition of any common ma-nure.

A correspondent in the " Museum Rustiaon" ascribes the neglect of this system to the following causes: 1. The poverty of many small farmers, who, holding their estates at a rack-rent, will not venture to lay out such a considerable sum on lands, which they may probably quit before their money will be returned. 2. Landlords, observing the parsimonious conduct of farmers, in working out the land, and thinking of no improvement beyond the present crop, are, in general, averse to this expdient, and will not grant permission to. their tenants to adopt it.

Bastard burn* baiting. This practice consists of burning the refuse product of the land, such as stubble, haulm, etc. upon the ground which produced them ; or whatever else is laid on it, for that purpose. It may be considered under four heads : 1. The burning of sedge on wet lands; a very old and successful practice. 2. Burning the stubble upon corn-fields; which is also an ancient and co mon method ; and though the ashes thus produced are light, and not abundant, yet the heat imparted ed to the ground, makes such a dressing better than four times the quantity of ashes of another kind. 3. The burning of any waste product on heaths and commons ; the benefit of which is not sufficiently known : this is performed by stubbing up the broom, or other wasto matter, piling it in heaps, and covering them with the earth that had been raised in digging to the roots; then burning the whole, and spreading the ashes on the ground, to be ploughed in. 4. The bringing of certain substances to impoverished land, and burning them there; such as sticks, stubble, haulm, or other waste matters of any kind. The principal advantage of this last method does not so much consist in the quantity of ashes produced, as in the enlivening warmth communicated to the ground, by such a number of small fires, which greatly contribute to promote its fertility.