Back in the days before monotonically increasing numbers of blades were used in safety razors, even very adept shavers suffered occasional nicks. The usual thing to do was touch a styptic pencil to the wound to stop the bleeding. Styptic pencils were sold in every drugstore – I don’t doubt that they still are. So closing small wounds with alum was both common and effective, and if you were shaving with a single bladed razor today, I daresay you’d use alum, too, rather than sport a large Band-Aid on your face. By the way, most young men would for some reason touch the styptic pencil to their tongue, and discover just what ‘astringent’ really meant.

I presume this is the Staff Report referred to:

What is alum, and will it make someone’s mouth shrink, like in the cartoons?