Some Biological Experiments with a Condenser Discharge Type of X-ray Tube

Abstract

THE question of the validity of the ordinary Bunsen-Roscoe reciprocity law for the biological effects of radiation has long been a moot one, and satisfactory evidence on either side has not been forthcoming. The principal reason for its absence has lain in the lack of availability of suitable physical equipment, which would permit a sufficient increase in the intensity of applied x-radiation to test the law over a very large range. Such equipment has recently been designed by Kingdon and Tanis and described by them (1). They have shown that a large and reproducible x-ray emission may be obtained by discharging a condenser through a tube containing a tungsten anode and a liquid-air-cooled mercury-pool cathode. The peak of current obtained through the tube under these conditions reaches several hundred amperes, so that the instantaneous x-ray intensity produced is extremely high. The availability of this radiation source has made possible the conducting of a number of radiation experiments with very careful...