So I'm rereading Edith Wharton's fluffy little novel The Glimpses of the Moon and I ran across this:

He sent a pneumatic telegram to Mrs. Nicholas Lansing to say that he would call on her that afternoon at four.

This is Paris, 1922 or so. What in the heck, I asked the longsuffering R who was trying to read his own book, could a pneumatic telegram be? Is it referring to the inflated tires of the bicycle messengers? For once R couldn't answer my question so I looked it up.

Check this out: The Internet of Tubes

How extremely cool.