If hydropower was available, which was mainly the case in spinning mills, it was used as advantage to drive fans, but otherwise there was no good alternative to human power in spite of ingenious experiments, including falling weights and turned up steel springs as a driving force. This meant that mechanical ventilation did not receive a proper breakthrough until the late 1800s, when the steam engine was to revolutionize the technological development. But before that the fuel-driven technology had time to be refined so much that both air flow and temperature could be regulated. Also, there were solutions so air could be purified and moistened before it came into the house.
September 8, 2015