slug.com slug.com

3 5

Charming! I wonder how well it worked.

Aircraft detection before radar, 1920-1940.

Naomi 8 Nov 22
Share

Be part of the movement!

Welcome to the community for those who value free speech, evidence and civil discourse.

Create your free account

3 comments

Feel free to reply to any comment by clicking the "Reply" button.

1

thought this was the first hearing aid

1

I can hear the sea.

2

Can you hear me now? It looks totally goofy but this was before the invention of a way to amplify sounds efficiently.

You can include a link to this post in your posts and comments by including the text q:153634
Slug does not evaluate or guarantee the accuracy of any content. Read full disclaimer.