Here’s a commercial from the 1930s for a product called “Life Lite,” an ultra-violet technology used for healing skin issues and more. The Life Lite looks a lot like a steam iron. 

A woman sets up the Life Lite over her sofa. Later, we see the woman laying on her sofa as if she were getting a suntan; the Life Lite is seen affixed to a pole, hovering over the woman's body, which is faced down. 

A girl smiles for the camera, showing what looks like open sores on her face. We are then told that three weeks-worth of salves were used on the girl's face, but to no avail. But things changed for the girl when she started to use Life Lite. 

A part of the Life Lite is opened up, apparently revealing the source of the utra-violet light. 

The Life Lite is then closed and passed over the girl’s face several times; the girl wears protective goggles during this process. Later, after seven days of using the Life Lite, the sores on the girl’s face are gone. 

In the final shot, the girl looks absolutely delighted, smiling, showing off her smooth, clean, sore-free face.