1. Twenty-two children with bone and joint tuberculosis were treated throughout the winter and spring with radiations from a high intensity carbon arc light.
2. In the majority of cases the blood counts rose under treatment. Our figures support the theory that the effect of the light upon the blood-forming tissues is a restoration of normal function, not a mere stimulation.
3. The children tended to gain weight while under treatment.
4. The favorable effect upon the local tuberculous lesion was marked.
5. We believe that our findings show that exposures to the radiations of the high intensity carbon-arc light are of value in the treatment of bone and joint tuberculosis, especially during those months when little sunlight is available.
6. While the value of this form of treatment seems to be well established many problems connected with its use remain to be solved.