EVOLUTION OF OUR KNOWLEDGE OF TUBERCULOSIS

Subtle, evasive, paradoxical, intricate and complex are terms that apply to the microscopic parasite which a recent writer¹ characterizes as "A Bug Full of Tricks." The early history of devastation wrought by this armored enemy of mankind is still preserved in the distorted joints and spinal columns of prehistoric skeletons and Egyptian mummies. The recent history is accumulating much faster than is the record of many other parasites that revolve about the microscopic or chemical and immunologic analysis.

The code of Hammurabi, written at least 2,000 years B. C., indicates some knowledge then of tuberculosis. Greek writers described the clinical features of tuberculous disease in the fifth century B. C. In the second century Aretaeus not only accurately described the clinical features but suggested routine treatment. In spite of their keen observations, Hippocrates and Galen recognized the hopelessness of a problem that appeared entirely occult. Galen probably never suspected