Reblogging because this is an interesting and forgotten tech.
It’s not generally known, but there were mechanical computers long before there were electronic computers. The Babbage engine is well known, even though Charles Babbage never completed a difference engine in his life. The Babbage engine was not an isolated machine. There were many other machines built to do a multitude of different jobs.
Here’s the wiki on the difference engine.
The page form the computer museum, which has one of the two competed machines.
Here are two tide predictors the NOAA used in the 19th and early 20th Centuries.
Engineer Guy explaining a mechanical computer.
How a fire control computer on a US Navy Battleship.
A mechanical calculator.
It’s amazing what can be done with gears, pulleys and levers.