American practice as regards the generation of suitable voltages and currents for deep therapy

In the past few years considerable strides have been made in the improvement and simplification of X-ray equipment both for medical and industrial purposes. At the same time it is a noteworthy fact that the demands of X-ray workers, are ever in advance of the apparatus at their disposal. It is for this reason that standardization is difficult, a design becoming almost obsolete as soon as perfection is approached. The comparatively sudden call for highly penetrative X-radiations of shorter wave-length, involving the maintenance of 200 000 volts at the tube terminals for continuous running, has imposed many difficult problems on the designer and manufacturer. In America these difficulties were to a great extent solved by research laboratories of large electrical corporations. The influence of sound engineering principles is, therefore, more noticeable in American practice than in that of any other country.