50. What shall we say in reply to the censure thrown on the process of permanent extension, in the memoirs of the academy, where it is charged with having been oftentimes productive of ulceration and even gangrene, in consequence of the pressure of the upper strap? What method can escape censure, if it be unskilfully pursued? What process will not be injurious, if mutilated and ill managed by ignorance or a want of discretion? To represent the thing properly, let us suppose the worst: a circular bandage, in consequence of being drawn too tight, produces mortification in the subjacent parts; must circular bandages be on this account entirely rejected? An unskilful hand, in an operation for cancer, opens the axillary artery; must we therefore cease to search under the arm-pit for schirrous glands? 51. Permanent extension is, say some, insufficient to overcome muscular action; it is opposing to a power equal to 1000, a resistance equal to only 100. But this force of the muscles, which is oftentimes so great at the time of reduction, diminishes gradually, by the pressure of the bandages, by the immobility of the limb, and, above all, by long continued extension; for a continued effort equal to 10, will soon perform what could not be effected by a temporary exertion of a force equal to 100. Let us pass over the more minute objections made against permanent extension, and search among the different modes of performing it, that to which practitioners ought to give a preference. 52. We may throw into two classes the general modes proposed by different authors for effecting permanent extension. Under the one are included those modes requiring simple means, such as straps, splints, &c. while the other embraces such as, from being complex, necessarily call for the use of different machines. 53. In the first class are comprehended: 1st, The method employed in the first instance by the Arabians, adopted afterwards by their successors in medicine, and proposed, at a still later period, by Petit, Heister, and Duverney, and which consists in fixing, at the head and foot of the bed, during the whole treatment, straps intended for the purpose of extension. 2dly, The mode of extension, adopted by many practitioners, which consisted in suspending to a strap fixed at the knee, and reflected over some suitable body, a weight proportioned to the power of the cause which it was intended to combat. 3dly, The ingenious idea of Bruninghausen, who, confining by a kind of stirrup, the diseased leg against the sound one, made the latter serve as a splint to retain the fractured limb on its proper line, and thus preserve its natural length. 4thly, Under this class also must we arrange the means employed by Desault, and which we will presently describe. 54. The second class of means invented for the purpose of making permanent extension, in fractures of the thigh, comprehends: