A hundred years ago, this youngster was overjoyed and enthralled by the “radio dancer”, a small toy which was placed on a radio speaker and would dance to the vibrations. The image is the cover of Radio News, December 1925, and the issue contains complete plans for making the toy.

The author of the article is none other than Hugo Gernsback himself. He was the publisher of the magazine and often offered his editorial views. He penned the construction article, and noted that one of his favorite toys as a child was a similar one that danced when placed on top of the piano. Here’s a description of such a toy from an 1881 book:

For Gernsback’s modern 20th century incarnation of the toy, he cautions that for sufficient vibrations, the radio set must have at least three tubes, and there needs to be a strong local station, in order to generate sufficient volume.  He notes that, of course, the dancer won’t work with a crystal set.