Ultraviolet radiation to have maximal germicidal effect should be at shorter wave lengths than those reaching the earth's surface from the sun—at around 254mμ instead of at the 290mμ to 320mμ which cause sunburn. Chemicals to block those longer wave lengths have been long since widely sold, but the successful search of Parrish et al (see page 276) for a chemical screen to germicidal wave lengths fulfills the need of a much more limited, though immensely grateful market—one which we hope will increase as a consequence of their efforts.
Orthopedic, cardiac, and neurosurgeons have been carrying out progressively longer operations, some of which have required the installation of large foreign objects in the patient as the primary objective of the procedure. All foreign materials left in the wound enhance the risk of infection, but some of these objects, such as the artificial valves used by cardiac and neurosurgeons, have shown