Left, catheters for the treatment of stones and disesases of the urethra; right, a boy held in the right position for the performance of the cutting of a stone and various instruments for this operation. Engraving with etching by R. Parr.

Licence: Public Domain Mark

Credit: Left, catheters for the treatment of stones and disesases of the urethra; right, a boy held in the right position for the performance of the cutting of a stone and various instruments for this operation. Engraving with etching by R. Parr. Wellcome Collection. Source: Wellcome Collection.