In South Africa many factors coincide in favour of a greater amount of ultra-violet radiation than that obtained in the lowlands of Central Europe. The greater altitude of the sun in South Africa results in a greater quantity of ultra-violet radiation and also in a further extension of the spectrum towards the short-wave end. The height above sea-level or large areas of the Union influences the ultra-violet radiation obtained in the same sense, i.e. increasing quantity and more effective quality. The intensity of the ultra-violet sky radiation is also considerable. This fact is particularly important in a country like South Africa where, due to the heating effect of infra-red and visible radiation, exposure to direct sunlight exercises a marked heating effect on the human body.
The role of the uranium-fission nuclear reaction as a convenient source of neutrons is reviewed. The application of neutron therapy to medical practice is reconsidered in the light of the probable availability of large quantities of neutron in the near future.
Two food-poisoning epidemics are descriptionbed, both of which were due to Salmonella dublin. The one outbreak was traced back to a bovine carrier excreting Salmonella in her milk. In the second outbreak the source of contamination was not identified.