In bleeding from the kidneys, alum whey is also useful, but "iron alum" (double sulphate of iron and ammonia) is a still more active remedy, which has, in my experience, acted better than many others. In cases where blood comes from the mucous membrane of the bladder or urethra, and when pain, straining, and undue frequency of micturition are present, I have known speedy benefit follow the use of alum injections (20 gr. to the pint) into the bladder.