In the 1800s cities used pneumatic tubes to transfer physical documents. Of course with the internet we no longer need these long tunnels, but that doesn't mean that they aren't fun to learn about how... continue reading
posted by winkler1 1 decade 4 years 12 months ago • 1,055 viewsOf historical value
Created: 1 decade 5 years 2 months 2 weeks ago
Updated: 7 years 11 months 3 weeks ago
Views: 2,235
Updated: 7 years 11 months 3 weeks ago
Views: 2,235