Lithotomy is the surgical removal of stones from the gall bladder. The lithotome was inserted up the urethra into the bladder. Its blade was then moved to grip small bladder stones, or to cut up larger ones so they could be pased out. It was a dangerous and painful operation and, without anaesthetic, speed was vital. Dr William Cheselden (1688-1752) could perform the procedure in les than a minute.
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