WOW-Never Heard of These Before!!!

[Super]

I am always amazed that I am still finding things I have never seen or heard of before. Double height sloped rails before but here they are. My question is....what engines were made to ride on these as they must have had side gears to engage those cogs in the rails to help it up the steep grade. Anyone have more info on these or other videos showing what engines ran on it?