Although a 'man engine' was never used at Wheal Friendship I think that it is interesting enough to explain how men left very deep mines elsewhere.
At Wheal Friendship they relied on long wooden ladders to exit from the mine.

The miner stepped on to the tiny platform attatched to the rods and was raised or lowered - depending on what "stroke" he stepped on. This transported him by the "lift" or "stroke" towards the next platform above where he stepped off. He then stepped on to the platform when it next appeared from above. He was raised to the next level above. He jumped off, waited for the next ascending stroke and stepped on again. This raised him to the surface in progressive steps. Here it was the distance between each platform - about 2 fathoms.

The "stroke" of the "man engine" was the distance that the large beam attached to the engine above rose or fell during a stroke. The weight of the rods themselves was counter-balanced using a "bob box" filled with rocks. This evened out the weight so that there was less work for the engine to raise or lower.

The ladder along side was for use when the man engine was not working. On these occasions the men had to climb out or walked out on the adit level.

The depths of many shafts were often well in excess of 1000ft deep. Start and cease work times were counted from the work face - not the shaft bottom! It was usual for every third man to keep his candle lit when using the "man engine". This saved on candles of course. Very short or stub ends were taken home to light their houses. They could not afford to let them be wasted.
Note the candles fixed to the front of the miner's hats with clay.
Normally the only light available was from these candles. The light provided here was by magnesium flash so as to take the picture. Immediately afterwards it was an abrupt return to darkness!
The miners had to buy their own candles - they were not supplied by the mine owners.