UV branding iron for newborns

The December, 1938 issue of Popular Science carried a glowing (heh) account of a UV branding iron used to scorch newborns' initials into their tender skin so that the nurses wouldn't mix up the babies.

A new hand-type ultraviolet-ray lamp makes it easier for nurses in a Brooklyn, N.Y., hospital to brand the initials of a new-born baby on his skin to prevent identification mix-ups in the hospital nursery. Soft ultra-violet rays pass through stenciled initials placed within the easily handled unit to tan the letters on the infant as well as on the mother. Harmless, the identification brand is said to remain visible for a period of two weeks.

New Sun Lamp Held in Hand Brands Babies (Dec, 1938)