Coal mining methods | PPT SlideShare
4. In Wales there is archaeological evidence of using coal in funeral pyres in bronze age, some yrs ago. Coal was mined in colonial America in the early 1700s and commercial mining first occurred around 1730 in Midlothian, ia. Coal cutting machine were invented in the 1880s. Before the invention, coal was mined from underground with a pick and shovel. In 1900 about 95% of the ...