Dibrugarh district personal grant from Dr. John Berry White after he retired as the civil surgeon of Lakhimpur district. The medical school, "John Berry White Medical School" was set up in 1900 at Dibrugarh, and thus this premier institute started its history, and marked a new era in education. Assam Medical College has the pride of having the first Radiology department in India, as in 1910 two X-Ray machine (One 10MA and another 15MA) was bought from England, only 15 years after the discovery of X-Rays by Professor Wilhelm Conrad Roentgen in 1895-96. These two were the first X-Ray machines in India.
Roentgen (unit) 1962 it was redefined. The CCU decided to define the SI unit of absorbed radiation in terms of energy per unit mass, which in MKS units was J/kg. This was confirmed in 1975 by the 15th CGPM, and the unit was named the "gray" in honour of Louis Harold Gray, who had died in 1965. The gray was equal to 100 rad. The definition of the roentgen had had the attraction of being relatively simple to define for photons in air, but the gray is independent of the primary ionizing radiation type, and can be used for both kerma and