[Turing_Machine]

> If you have to manually dig a few hundred meters down to even reach coal

You don't, though.

https://www.eia.gov/energyexplained/coal/how-much-coal-is-le...

53% of the recoverable coal reserves in the United States can be recovered with surface mining.

[ceejayoz]

"Surface mining" involves quite a bit of industrial-scale digging. For example: https://en.wikipedia.org/wiki/Hambach_surface_mine goes down 1,640 feet from the surface and looks like https://upload.wikimedia.org/wikipedia/commons/e/e8/Bannerak....

[Turing_Machine]

As I noted in the other post, the Big Hole in South Africa was dug to a depth of 240 meters by hand.

Coal mines of that depth nothing special, even with 19th Century steam technology.

https://en.wikipedia.org/wiki/History_of_coal_mining

"By 1856, the average depth in the Borinage was 361 meters (1,184 ft), and in 1866, 437 meters (1,434 ft) and some pits had reached down 700 to 900 meters (2,300 to 3,000 ft); one was 1,065 meters (3,494 ft) deep, probably the deepest coal mine in Europe at this time."

[ceejayoz]

"thanks to the good pumping system" (guess what powers that) and "by the late 19th century the seams were becoming exhausted" indicate the practical limitations faced by that.

[Turing_Machine]

> "thanks to the good pumping system" (guess what powers that)

In the 19th Century?

Steam engines that burn part of the extracted coal. What else?

> by the late 19th century the seams were becoming exhausted

Those particular seams, maybe. They're not the only seams, dude.

I think we're done here.