Do You Know Jack?
Jacks - the unsung heroes of wheeled transport!
This is an old cast iron Simplex 310A railroad jack. It's an actual Simplex-branded one, not some other heavy ratchet jack that people call Simplex because that's become a generic term in some areas. It's marked as having a 14in lift. Google tells me these were rated for 15 tons (I'm sure that's marked on it somewhere, I just didn't see it during my quick look). This one is now doing farm/construction duty, holding up one corner of a Caterpillar loader.
Check out that sweet profile!
The ability to safely lower a heavy load was one of the big selling points of the original Simplex jacks. I think the lever under the handle sets the direction and you pump until it's where you need it. There are other heavy-duty ratchet jacks where lowering requires resetting a lever for each notch down, which would get old pretty fast if you had it cranked all the way up.
Up close and personal
It has a second, lower lift on the side. The small lever by the base allows the jack to tilt, though I don't know the condition of that part. You can also see that this model has two handle positions, which you'll appreciate if you've ever had to swing/turn a tool in a tight space.
A 1945 catalog on archive.org lists the full kit at $62. That's around $900 adjusted for inflation in 2021.