810. _Recovery from Suffocation, &c._--There are many occasions of danger, on which a person who can hold breath for a minute or two, may save the life of another. The best preparation for rendering such assistance is, by breathing deep, hard, and quick, (as a person would do after running,) and ceasing with his lungs full of air; he will then find himself able to hold his breath more than twice as long as he would without such preparation. If in a brewer's fermenting vat, or an opened cess-pool, one man sinks senseless and helpless, from breathing the foul air, another man of cool mind would, by the above preparation, have abundant time, in most cases, to descend by the ladder or bucket, and rescue the sufferer, without any risk to himself. In entering a room on fire, a knowledge of this fact may be useful. The following precautions should also be regarded. Avoid all unnecessary exertion; go coolly and quietly to the spot where help is required; do no more than is needful, leaving the rest to be done by those in a safe atmosphere. In case of _choke-damp_, as in a brewer's vat, hold the head as high as may be: in case of a fire in the room, keep the head as low as possible. If a rope be at hand, fasten it to the person who is _giving_ help, that he may be succored, if he venture too far. Many deaths happen in succession in cess-pools, and similar cases, for want of this precaution. It is hardly needful to say, do not try to breathe the air of the place where help is required. Yet many persons fail, in consequence of forgetting this precaution. If the temptation to breathe be at all given way to, the _necessity_ increases, and the helper himself is greatly endangered. Resist the tendency, and retreat in time. Be careful to commence giving aid with the lungs _full_ of air, not empty; for the preparation consists chiefly in laying up for the time, in the lungs, a store of that pure air which is so essential to life. 811. _Thunder Storms._--The safest situation during a thunder-storm is the cellar; for when a person is below the surface of the earth, the lightning must strike it before it can reach him, and will probably be expended on it. Dr. Franklin advises persons apprehensive of lightning to sit in the middle of a room, not under a metal lustre, or any other conductor, and to place their feet upon another chair. It will be still safer, he adds, to lay two or three beds or mattresses in the middle of the room, and to place the chairs upon them. A hammock suspended with silk cords would be an improvement on this apparatus. Persons out of doors should avoid trees, &c.