Fire-Escape, a contrivance for the purpose of rescuing persons in imminent danger from fire.

In the Annual Register for 1775, an account is given of a machine for saving persons and effects from the flames. It consists, 1. Of a pole of fir, which may be of any convenient length, being about five inches in diameter at the bottom, and at the top or smallest end, about three inches. At the distance of three feet from the top, is a mortice through the pole, to which a pulley is fixed, that is nearly of the Same diameter as that part of the pole. 2. A rope about three-fourths of an inch in diameter, and twice the length of the pole, at one end of which is a spring-hook, to pass through the handle of the basket, when used ; it is put through the mortice over the pulley, and drawn tight on each side, nearly to the bottom of the pole, where it is secured till wanted. 3. A basket, which ought to be of strong wicker-work, three and a half "feet long, two and a half feet wide, rounded off at the corners ; and four feet deep, rounding every way at the bottom. To the top of the basket is fixed a strong iron curve, or handle, with an eye or ring in the middle: a small cord about the length of the pole, is likewise fastened to one side of the basket, near the top. - These being the principal parts, there are also several straps, etc. for securing the poles from sliding; of which the reader will find a minute account in the volume before quoted. This contrivance can be raised, and two or more persons may be taken out of the upper windows of a house, and let down safely in the street, within the space of thirty-Jive seconds, or in little more than half a minute.

A machine for this purpose has lately been invented by the Rev. Dr. Nicholas Collin, of Philadelphia, the following description of which we have abridged from the 4 th vol. of the Transactions of the American Philosophical Society.— A strong wooden case is erected near the end of a rectangular stage of solid planks, mounted on four wheels (with locks to secure the latter when the machine is employed), for the reception of an upright round shaft. This shaft is moveable in the case, by means of two ropes fastened to its foot ; which, after passing over two puliies or sheaves in the top of the case (one being on each side), are fastened to two windlasses, by winding or unwinding which, the round shaft is raised or lowered. On the top of this upright moveable shaft, is an iron fork with a transverse pin, on which rolls a fever with unequal arms. The longest arm is directed towards the fore-end of the stage, which it ought not to exceed in length, un-less the hinder-end be proportion-ably loaded. The shortest arm is lowered or raised by a rope fastened to its extremity, which reaches to the posterior end of the stage, and may be pulled either by men or by a windlass: or, a compound pulley may be substituted for the rope. To the fore-end of the longest arm of the lever, a basket is suspended, by three iron rods, for the reception of persons or goods in danger, and which, by loosening the hinder rope, is thus lowered. As; however, in great elevations, the basket cannot reach the ground, a rope is fastened to it, by which persons or goods may descend. - Dr. Collin mentions a larger and a smaller kind of this machine, by the former of which twelve persons may be let down, and by the latter four. As he has not specified any dimensions, we suppose that they are to be proportioned to the height, at which houses and other buildings are in general erected, and to the number Of persons the machine is intended to rescue. - We cannot, on this occasion, omit to point out the great utility of those fringed ropes which should be fastened to the foot of a bedstead, and extend to a sufficient length, to descend by them, in case of fire, through a window : they are sold by several rope-manufacturers in town, generally at two shillings per yard.