A chimney sweep is a worker who clears ash and soot from
chimneys. The chimney uses the pressure difference caused by a
hot column of gas to create a draught and draw air over the hot
coals or wood enabling continued combustion. Chimneys may be
straight or contain many changes of direction. During normal
operation a layer of creosote builds up on the inside of the
chimney restricting the flow. The creosote can also catch fire,
setting the chimney and the building alight. The chimney must be
swept to remove the soot. This was done by the master sweep. In
the United Kingdom, the master sweeps took apprentices, who were
boys from the workhouse or bought them from their parents and
trained them to climb chimneys. Boys as young as four climbed
hot flues that could be as narrow as 9 inches square. Work was
dangerous and they could get jammed in the flue, suffocate or
burn to death. As the soot was a carcinogen, and as the boys
slept under the soot sacks and were rarely washed, they were
prone to Chimney Sweeps Canc