Every physician is necessarily interested in the chemistry of rubber because this is one of the materials which enter into numerous articles and devices daily applied in medical and surgical practice. Experience teaches the unlike qualities of different types or brands of rubber. Some of them retain their original elasticity for a long time under the imposed conditions of usage, while others speedily deteriorate into brittle and useless scrap despite the various precautions of preservation that are embodied in familiar directions. The economic aspect of the quality of rubber goods offered for sale to the medical profession is an important one, because the expenditures in this department of the physician's equipment as well as of the supplies for the sick room and hospital are not inconsiderable.
The time is arriving when the purchaser of rubber will demand some reliable information as to the quality of the product which he is