The American journal of the medical sciences (1827)
[Thorofare, N.J., etc.] Charles B. Slack [etc.] · leaf 161
181 4.] Morton, Hospital Bed-Elevator and Carriage. 159 The apparatus consists, as will be seen by a reference to the wood-cut, of a double truck, the upper one elevated by a series of cams which run … upon a narrow iron track ; a long right and left screw, worked by an end- less chain upon a crank at one end raises and depresses the cams. The apparatus is made of oak, and the hinges of brass, the wheels are sup- ported by steel pins. By experiment it has been found that four hundred pounds can…
Medicine
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