Specification of Alfred Vincent Newton : artificial legs.

  • Alfred Vincent Newton
Date:
1867
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Alfred Vincent Newton : artificial legs. Source: Wellcome Collection.

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    Newton s Improvements in Artificial Legs. slightly enlarged towards each end to enable the fulcrum bolt to vibrate in it laterally that tbe foot may turn slightly. A spring/* is fitted and secured to the upper part of the segment e, and the front end of it curves down to rest on the bottom of the inside of the foot and extends into the cavity of the 5 hinged toe piece 6, and the rear end of the said spring curves down into the cavity of the heel and rests on the bottom thereof, so that when the foot in walking is thrown forward and the heel first strikes the ground the spring will permit it to yield upward, and as the foot falls back by the forward motion of the body the front part of the spring will yield and 10 allow the front part of the foot to yield upwards, and finally the toe piece will yield upwards, thus causing the foot to yield and return to the oiiginal position as the natural foot does in walking. To give greater power of resistance to the heel it is preferred to make the spring/ double at the rear end, as represented, the upper leaf being at some distance above the lower 15 leaf, so as to be brought into action in case considerable pressure is made on the heel. The parts of the foot on which the spring bears are lined with leather or other substance more yielding than wood. The leg is formed in two parts g and h, and of a tubular form fitted to slide the one within the other, like the tubes of a telescope ; in this way the requisite strength with very 20 little weight is obtained. The lower end of the lower tubular part g is fitted to slide on the leg piece g1, which connects with the foot, as before described, and a coiled spring a1 is inserted in the tube and above the leg piece g1 to yield slightly when the foot is brought to the ground, and thus to avoid any disagreeable concussion on the stump of the amputated limb. The lower end 25 of the leg piece g1 is so formed, as represented, that it can be firmly secured to the upper part of the segment e by a screw i, which at the same time secures the spring / which is interposed, as represented, between the lower end of the leg and the segment e. There is a right and left handed screw j within the tubular leg pieces, and parts of each tube piece are threaded to fit the 30 threads of the screw ; at about the middle of its length the screw shaft is suitably formed as at Jc, so that it can be turned to increase or shorten the length of the leg. Binding nuts are fitted to both ends of the screw to hold the parts firmly together when the required length has been obtained. The tubes g and h are slotted to give access to the screw and to the binding nuts 35 so as to admit of turning them ; other and equivalent means may be sub¬ stituted for adjusting the length, and for holding the parts firmly when set, and to prevent the one part from turning on the other. The upper end of the tube h is solid and bifurcated, the two branches l, l, forming about a semi¬ circle, and their upper ends are fitted to turn on the ends of an axle m, which