A knowledge of the locality thus obtained will be found of great advantage in case of a fire breaking out. Indeed all firemen, especially those having the charge of engines, should be instructed carefully to examine and make themselves acquainted with the localities of their neighbourhood or district. Such knowledge will often prove valuable in emergencies; the proprietors or tenants of the property on fire being sometimes in such a state of alarm, that no distinct intelligence can be got from them. When an engine is brought to a fire, it ought to be placed as nearly as possible in a straight line between the supply of water and the premises on fire; taking care, however, to keep at such a distance from the latter that the men who work the pumps may be in no danger from being scorched by the heat, or of being annoyed by the falling of water or burning materials. Running the engine close upon the fire serves no good purpose, except to shorten the quantity of hose that would otherwise be required. The addition of twenty or thirty feet of hose makes very little difference in the working of the engine, and, when compared with the disadvantage of the men becoming unsteady from the idea of personal danger, is not even to be named. Indeed, if the engine be brought too near the fire, there is danger of the men quitting the levers altogether. I may also add that, both for the safety of the hose and the convenience of the inhabitants, the engine should be kept out of the way of people removing furniture. When the hose is attached and the engine filled with water, the man who holds the branch-pipe, accompanied by another, should get so near the fire, inside the house, _that the water from the branch may strike the burning materials_. If he cannot accomplish this standing, he must get down on his hands and knees and creep forward, those behind handing up the hose. A stratum of fresh air is almost always to be depended on from six to twelve inches from the floor, so that if the air be not respirable to a person standing upright, he should instantly get down. I have often observed this fact, which indeed is well known; but I once saw an example of it which appeared to me to be so striking, that I shall here relate it. A fire had broken out in the third floor of a house, and when I reached the top of the stair, the smoke was rolling in thick heavy masses, which prevented me from seeing six inches before me. I immediately got down on the floor; above which, for a space of about eight inches the air seemed to be remarkably clear and bright. I could distinctly see the feet of the tables and other furniture in the apartment; the flames in this space burning as vivid and distinct as the flame of a candle, while all above the smoke was so thick that the eye could not penetrate it. The fire had already burst through three out of five windows in the apartment, yet, when lying flat on the floor, no inconvenience was felt except from the heat.