Preservation of Fossil Bones

Abstract

THE difficulty of preserving fossil bones found in deposits of the later phases of the Ice Age or more recent beds is known to collectors and museum curators; often enough the bones crumble to dust after a night's exposure to the air. Much can be done by immediate attention to preserve such relics for examination and permanent exhibition, and a paper on the “Bakelite Impregnation of Fossil Bones” by H. W. Nichols and Phil C. Orr, of the Field Museum of Natural History in Chicago, ought to be widely known (Museums J., vol. 32, p. 47, May 1932). In the Field Museum, most of the older impregnating materials have been tried, paraffin, glue, gum arabic, shellac, wolfite and several mastics. In some respects these are all deficient. Of the older materials, shellac was found to be the most satisfactory, but Dr. Case's bakelite process is better than any other. Broken bones are cemented with a mixture of plaster of Paris and dextrin, and when the cement is dry, the bone is placed on a screen and lowered gently into a tank of bakelite reduced to a suitable condition of fluidity by the addition of bakelite thinner. The bones thus treated are allowed to dry and the surface cleaned. The greater number of bones require no further treatment, but if a specially strong surface is required the bones may be baked at a temperature of about 208° F. or more, when the bakelite, undergoing polymerisation, gains full strength and becomes no longer soluble in the thinning solution.