FLANNEL, a kind of woollen stuff, composed of a woof and warp, and woven after the manner of baize. Various theo ries have been adopted to prove the uti lity of flannel as an article of dress : it is unquestionably a bad conductor of heat, and on that account very useful in cold weather ; this is accounted for from the structure of the stuff; the fibres touch each other very slightly, so that the heat moves slowly through the interstices, which being already filled with air, give little assistance in carrying off the heat. On this subject Count Rumford has made many experiments, from which it should seem, that though linen, from the appa rent ease with which it receives dampness from the atmosphere, appears to have a much greater attraction for water than any other, yet that those bodies which re ceive water in its unelastic form with the greatest ease, or are most easily wet, are not those which in all cases attract the moisture of the atmosphere with the greatest avidity. " Perhaps," says he, " the apparent dampness of linen to the touch arises more from the ease with Which that substance parts with the wa ter it contains, than from the quantity of water it actually holds ; in the same man ner as a body appears hot to the touch in consequence of its parting freely with its heat, while another body, which is really at the same temperature, but which with holds its heat with great obstinacy, affects the sense of feeling much less violently. It is well known, that woollen clothes, such as flannels, &c. worn next the skin, greatly promote insensible perspiration. May hot this arise principally from the strong attraction which subsists between wool and the watery vapour which is con tinually issuing from the human body ? That it does not depend entirely on the warmth of that covering is clear ; for the same degree of warmth, produced by wearing more clothing of a different kind, does not produce the same effect. The
perspiration of the human body being ab sorbed by a covering of flannel, it is im mediately distributed through the whole thickness of that substance, and by that means exposed, by a very large surface, to be carried off by the atmosphere ; and the loss of this watery vapour, which the flannel sustains on the one side, by eva poration, being immediately restored from the other, in consequence of the strong attraction between the flannel and this vapour, the pores of the skin are disen cumbered, and they are continually sur rounded by a dry and salubrious atmo sphere." He expresses his surprise, that the custom of wearing flannel next the skin should not have prevailed more uni versally. He is confident it would pre vent a number of diseases : and he thinks there is no greater luxury, than the com fortable sensation which arises from wear ing it, especially after one is a little ac customed to it. " It is a mistaken notion," says he, "that it is too warm a clothing for summer. I have worn it in the hot test climates, and at all seasons of the year ; and never found the least inconve nience from it It is the warm bath of perspiration, confined by a linen shirt wet with sweat, which renders the summer heats of southern climates so insupporta ble ; but flannel promotes perspiration, and favours its evaporation ; and evapo ration, as is well known, produces posi tive cold."