Lightning, a vivid, bright flash of fire, which suddenly appears in the atmosphere, and instantly, vanishes: it is sometimes attended with heavy clouds and thunder; but often occurs while the sky is serene, especially in sultry summer evenings.

The phenomena accompanying this meteor are always surprizing; but, in many cases, truly terrific :-various causes have been assigned by philosophers, with a view to explain them. Some suppose lightning to arise from inflammable matter, consisting of the sulphureous and nitrous vapours exhaled from the earth, and carried into the atmosphere; whence the more fiery particles are separated, so that they explode by the concussion of two clouds, or some other cause, in various directions of a greater or less extent, according to the strength and quality of the materials. Others conjecture lightning to be formed by the fermentation of sulphureous matters with the nitrous acid. It is, however, now generally understood to be an electrical phenomenon.

In common with electricity, lightning possesses the property of burning and dissolving metals ; it rends bodies, often deprives persons of sight, and sometimes extinguishes the vital principle ; divests magnets of their virtues, and reverses their poles. Indeed, there is no appearance in Nature, that presents a greater diversity to the contemplative mind; for each flash is widely different from another nor are its effects alike fatal.

When the igneous meteor exhibits a deep red colour, it is seldom accompanied with dangerous consequences; but, if the flashes be bright, pale, and in a zig-zag direction, destruction generally marks their course. The" most mischievous form, however, winch lightning assumes, is that of fiery balls: wherever such masses descend, they burst, and occasion extensive damage.

As lightning uniformly strikes the most elevated objects, such as lofty trees, steeples, and particularly the masts of ships and chim-nies of houses, various expedients have been contrived, in order to divert, or at least break, its force. These efforts of human ingenuity were first published, or recommended to public notice, by Dr. Franklin ; and, from their acknowledged Utility", CODUCTORS are now generally adopted:-We have already pointed out the most judicious form of constructing them, in pp. 47 and 48, of our 2d volume.

Another method of preventing the fatal effects of lightning, con-' sists in the artificial attraction of electrical matter from the clouds, by means of a Kite. Having, under that article, stated the manner in which this useful machine should be constructed, we shall now communicate a tew directions for its proper management.

In order to adapt the electrical hilt to the 'important purpose of affording security during a thunderstorm, especially when persons are exposed to its influence in an open ' field, it will first be requisite to fix a thin iron point, about 12 inches long, on the top of the machine, marked a (see p. 51); then to surround the whole leading string with a thin iron wire, which should be previously connected with the metallic point. Having made these preparations, a strong wooden staff, three or four feet long, must be procured, and likewise furnished with a firm iron point on its lower extremity, and a similar ring on the top, so that it may also serve as a walking-stick. But there ought also to be a stronger iron wire affixed to this staff, either in a perpendicular or serpentine direction, so as to communicate with both the ring and the lower end, which is to be forced about 12 or 18 inches into the ground, according to its softness; in order to support the whole machine, while suspended in the air.- On the approach of a thunder-storm, and before it actually breaks out, it will be advisable, first, to drive the staff sufficiently deep into the ground, so that its strength may be adequate to the force of the wind ; then to fly the kite thus prepared with the greatest expedition ; and lastly, to fix the string, with its accompanying wire, to the iron ring of the staff before described. In this easy manner, all danger of being struck by, lightning may be effectually averted; but it ought to be remarked, that no person should afterwards approach this electric staff; though any number of people working in the fields, even diametrically opposite to the floating body of the kite, will be protected by its conducting power; provided they keep at the distance of twenty yards, at the least, from the staff to which it is fixed.- Nor will it be proper to fly the machine during a shower of rain, or very boisterous weather.

Persons struck with lightning; may, in many instances, be restored by proper and timely applications. In slighter cases, where particular limbs are affected, the wounded part has been cured by washing it with a solution of sugar of lead.- According to Tod e, considerable relief has been derived from applying opium to the painful part of the breast, after being hurt with lightning; and a person, wounded by this meteor, was perfectly cured in the course of ten days, by the application of ley to the part affected, and by the internal use of carbonate of pot-ash, or fixed vegetable alkali dissolved in water.—Should, however, any person be apparently killed by such an accident, he ought by no means to be neglected, or precipitately committed to the grave; for we are persuaded, that many might be restored, if proper resuscitative means were employed.

In general, there are no external marks discoverable, when the body has been injured by a flash of lightning; though sometimes red streaks appear on different parts, especially on the chest and arms, in which the patient, after recovery, experiences a sense of burning heat.-The first step should be, to remove the body from the farther influence of mephitic air of the place, where the unfortunate blow was infiicted. Clothes and bandages of every kind must be removed ; the body placed in a reclining posture; and the head raised, somewhat leaning to the right side: thus the subject is tobe covered with warm blankets or cloths; while both the doors and windows are opened for admitting fresh air.

Resuscitatives : Sprinkle the face with cold water, put the whole body up to the neck, if convenient, in the earth-bath, where it should be kept for several hours, till certain signs of returning life appear : or expose the subject, if robust, to the influence of the shower-bath ; apply cold poultices to the head; cloths dipped in vinegar to the pit of the stomach; and gentle friction, which should be resorted to, alternately, with the sprinkling of Cold Water, from the beginning of the process; at first with great caution, over the lower extremities, and gradually extending it upwards to the left side of the body.

In particular cases, where the means before stated prove ineffectual, it will be advisable to open a vein, or to electrify the patient, by directing the shocks through the breast, so that this fluid may pervade the heart.- Meanwhile, pure air may be blown into the lungs (see vol.ii. p. 190); and, if anxiety appear to prevail, blisters should be applied to the chest.

When signs of returning life become evident, the mode of treatment before pointed out, must be continued for some time, though with great moderation. The cloths applied to the pit of the stomach, should now be dipped in wine, or warm vinegar ; common poultices applied to the injured parts; and emollient clysters may be occasionally given.- Lastly, when the patient is able to swallow, a mixture of wine and water, or balm-tea, may be safely administered.

Dr. Franklin suggests to those persons, who are apprehensive of danger from lightning, the propriety of sitting in the middle of a room on one chair, and to lay their feet on another; provided they be not placed beneath a metal lustre suspended from the ceiling by a chain. He farther observes, that it is still safer to fold two or three mattresses-or beds in the middle of an apartment, and to place the chairs upon them j for, as the former do not conduct lightning so readily as the wall, the flashes cannot penetrate their substance.- But the most secure place, in his opinion, is a hammock, suspended by silken cords, in the centre of a room.- The curious reader, who wishes to obtain farther information respecting electrical meteors, will be amply gratified, by perusing Dr. Franklin's Experiments and Observations On Electricity (4to. 1769, 10s. 6d.) ; and Dr. Priestley's History of Electricity, 4to. in which this interesting subject is perspicuously-treated.

The effects of lightning are frequently not less fatal to vegetable productions. Wheat-plants are peculiarly susceptible of this injury; and Mr. Tull is of opinion, that not only their health is thus greatly impaired, but also their immediate decay, is thereby often occasioned. Such consequences, he observed, were evident from the black spots or patches in a field of corn, especially in those summers which were visited by frequent thunder storms: and he adds, that there is no remedy against this evil.

Forest-trees, in particular, experience similar blasts; and, on sawing them, numerous instances have occurred, in which they were found cracked, split, or otherwise muti ated by lightning.—Dr. Darwin conjectures that vegetable; are affected by this meteor in a manner similar to that, when their succulent shoots are frozen; that is, their vessels burst, as the lightning passes through them, in consequence of its expansive power.