A fitted case of oiled leather holding a physician’s working instruments: a set of lancets in graded widths for opening abscesses and venesection, a curved bone saw for amputation, a fine-toothed trephine for skull work, long-handled forceps and tooth-pullers, scalpels of drawn steel, slender silver probes, an arrow spoon for drawing out embedded points without widening the wound, a pair of wound retractors, cauterizing irons, a tourniquet of waxed cord, and a small brass basin. The steel is drawn thin and hardened by a smith who understands the craft; the edges must be honed on stone between uses, and the whole case is boiled in water or wiped with spirits before serious work. Such instruments are expensive, and their loss is grave; a surgeon will not lend them casually, and an apprentice handles them with the reverence owed to tools on which lives turn.
The kit is the difference between a physician who can bind and dose and one who can cut, set, and amputate. Routine treatment — bandaging, poulticing, splinting, light suturing — needs only medical supplies and a trained hand. But when a limb must come off to save a life, or a skull must be trephined to relieve pressure, or a grave internal wound must be reached, no amount of supplies substitutes for the right steel. A barber-surgeon without the kit is a dresser of wounds; with it, a master of the darker half of the craft.