VOL. XLII.] PHILOSOPHICAL TRANSACTIONS. ' 70/ 



SO by 2 hooks fixed on the backside of it ; and when one end of it stands on 

 the ground, the other stands high enough to become a fulcrum, or support of 

 a lever bb, which is fixed on a roller b, by a large wood screw, which turning 

 sideways as well as with the roller, it obtains a circumrotatory motion; so that 

 it will serve to reduce a luxation either backward, forward, or downward. 



The roller on which the lever is fixed, is just the diameter of the depth of 

 one of the boxes, into which are driven 2 iron pins, the ends of which are re- 

 ceived by the 2 sides of the box, which are 1 inch thick. 



The lever is 2 feet 4 inches, and is cut off and joined again by 2 hinges c, to 

 fold up so as to be contained in the boxes. On the backside of it is a hook, to 

 keep it straight ; the other end is to hang over the roller about 14. inch, which 

 is to be excavated and covered with buflP leather, for the more easy reception of 

 the head of the os humeri. 



Two iron cheeks dd are screwed on each side of the lever, to receive through 

 them an iron roller e, which has 2 holes through it, to receive 2 cords coming 

 from a brace f, fixed on the lower head of the os humeri ; for on no other part 

 of the arm above the cubit can a bandage for this purpose be useful ; for, if the 

 surgeon applies it on the muscular part of the arm, it never fails slipping down 

 to the joint, before you can extend the limb. 



The iron roller has a square end, on which is fixed a wheel g, within the 

 cheek, notched round, which works as a rotchet on a spring ketch under the 

 lever, by which it is stopped, as you wind it with a winch ; and may at pleasure 

 be let loose, as there shall be occasion for it, by discharging the ketch. 



He next describes the brace f, which, compared with common bandages, is 

 of more consequence than can easily be imagined by unexperienced persons. It 

 consists of a large piece of buff leather, sufficient to embrace the arm, sewed 

 on 2 pieces of strong iron curved plates, riveted together, one of them having 

 an eye at each end, to fasten 2 cords in ; the other is bent at the ends into 2 

 hooks, which are to receive the cords, after they have crossed over the arm 

 above. 



In order to keep the patient steady in his chair from coming forward, or 

 letting the scapula rise up, on depressing the lever, after the limb is drawn for- 

 ward by the winch, there must be fixed over the shoulder a girth with 2 hooks 

 at the ends of it, long enough to reach to the ground on the other side, 

 where it must be hooked into a ring i, to be screwed into the floor, for that 

 purpose. 



4x 2 



