By trituration of the pure clay. Give the general action of Alumina. Through the spinal nerves Alumina acts on the colon and rectum, producing great dryness of their secretions ; it also produces profound prostration of the cerebro-spinal nervous system. What is a feature that runs all through Alumina ? Dryness of membranes, the conjunctiva, the nose and the intestinal tract are all very dry. Give grand characteristics of the drug. 1. Dark complexioned, spare, dry, thin people [ Calcarea opposite].