Modern dermatological methods are responsible for the introduction of various forms of applications which are neither ointments nor lotions, and which may or may not be fatty. Specialists find that a vehicle which has not itself any action upon the epidermis is hard to discover. Dr. Unna is one of the most fertile innovators in this line. It was he who introduced the now universally known jellies, composed essentially of glycerinated water solidified with gelatin and mixed with a medicament suitable for the diagnosed disorder. The best known is zinc-jelly or zinkleim (i.e., zinc glue), for which the formulae are -

All by weight. Soak the gelatin in the water overnight, and afterwards dissolve by the heat'of a water-bath. Triturate the oxide of zinc with the glycerin, and mix intimately with the warm gelatin solution. Add water, if necessary, to make the weight 20 to 21 oz.

These gelatin pastes are applied while hot to the skin with a brush ; they are supposed to exert a highly cooling effect upon the skin, are as protective as fatty compounds, and do not interfere with the perspiration. While the gelatin is still warm upon the skin a muslin bandage is wound round, and the jelly penetrating into the meshes of the muslin- of which several layers are applied- gives to the disordered part quite a firm, slightly compressing case.

The following are other prescriptions of Unna's which it is useful for dispensers to know. All the ingredients are to be taken by weight: