17)  Downtown Battleship?  That's right, your eyes aren't deceiving you:  in 1917, the Navy built a nearly full-scale battleship in downtown New York City to aid in the recruitment effort that would soon be vital in WWI.  The ship had a fully-functioning crew and people came out at all times of the day and night to see the crew perform their duties.  

18)  The First Ghost Photo?  The first potentially authentic ghost photo was taken in 1891 by a young woman named Sybell Corbet while she was visiting the library at the Combermere Abbey in Cheshire, England.  You'll notice the faint outline of a man sitting in the chair in the foreground.  Lord Combermere had died a few days earlier in a riding accident and this photo was taken during his funeral when the entire staff was out of the home.  It's enough to make you wonder...

 

19)  Let's Hit the Road, Ethel!  Before companies fully-developed the concept of the mobile home or RV, various handymen and inventors played around with customizing their own versions, as we see here in this amazing photo from 1926.  

20) Getting in a Workout on the Titanic.  The Titanic aimed to do everything over-the-top and as lavish as possible, and this meant a state of the art gym as well!  We don't often think that people 100 years ago really used gym equipment given how active they were, but this 1912 photo gives a unique glimpse in to what early gyms looked like.