When Machines began to Replace Men Part 1
Ron takes a look back at the evolution of steam engines and associated products
For thousands upon thousands of years men relied on their own strength and effort, along with that of animals, to do work. Of course those in position of power used the work of others, often using them as slaves. The Greeks and the Romans for all their civilisation made no progress towards taking the physical burden of work from men, they even failed to make the best use of animals in this regard. Very surprisingly, however, the Greeks did play with the concept of steam power and a Greek mathematician, physicist and engineer, Hero of Alexandria, invented and built Hero's wheel which was, in effect, a steam turbine. Unfortunately for the next many generations, people at that time failed to appreciate the potential of what they had and, after using it for a while to raise temple doors, it was discarded.
In the 1400s and 1500s there was a demand for power to grind corn and we saw the development of windmills and, more significantly, water wheels. From the fifteenth century through to about the end of the eighteenth century there was a mini ice age (which, incidentally, no one seems to know why it occurred. Could it happen again?) At this time the technique for producing sheets of glass was improving and the cold weather led to a demand for glass windows. (This cold period also saw the widespread use of buttons on clothing for the first time) The demand for glass in turn led to the requirement for a lot of heat in the manufacturing process, that demand was initially satisfied by burning wood. The rate at which the country's woods were being consumed alarmed the king, especially as he had a requirement for wood to build his naval ships. King James finally banned the use of wood in the manufacture of glass and the search for alternatives led to the use of coal. It was soon discovered, however, that the best coal was beneath the ground but many attempts to access this store were frustrated by the tendency of the mines to flood. Pumps were designed driven by horses to lift the water from the mines, but the power demanded was such that the number of horses required imposed serious limitations on what could be achieved.
A number of factors came together at this time to contribute towards the final solution to this problem:
In Germany a man by the name of Guerniche managed to create a vacuum with a small air pump. In 1662 Edward Somerset used condensing steam to create a vacuum to suck water up and then used steam pressure to force it out to produce a fountain. A Frenchman, Denis Papin came to London in 1675 to escape the strict religious attitudes in France, he spent most of his time in Britain until his death in 1707. He worked with Robert Boyle (of Boyle,s Law fame). Papin used a vacuum created by allowing steam to condense to raise a weight. He demonstrated a steam engine of sorts and, in 1704, a steam boat. His most famous invention, however, was his 'digester', in effect a pressure cooker. Whilst he clearly had some understanding of the potential of steam he seemed to lack the necessary drive and enthusiasm needed to see his ideas through into practical engines.
The Christian Churches were opposed to science, fearing that it would contradict some of their teachings, it was a time when they acquiesced with, if not condoned, the persecution of witches as agents of Satan. The Anglican gentry considered science and industry as beneath them so they slipped into an intellectual stupor. Following the restoration of the monarchy after Cromwell, loyalty to the Anglican Church was demanded, an attitude primarily intended to be anti-Catholic but applied to everybody. Those that did not conform were termed 'Dissenters' and were stripped of many rights. The midlands, the north of England and Scotland were more tolerant and apparently less opposed to science so that there was a drift of dissenters northwards. Many of them were very intelligent and were interested in science and in the new industries.
The concentration of these people in areas outside of London, especially in Glasgow was to have a significant impact on the problem of removing water from the mines and, as a consequence, on the whole future of global industry.
Thomas Savery was interested in Somerset's and Papin's work with vacuum and saw the possibility of using this to 'suck' water from the mines. In 1698 he developed a system of generating vacuums repeatedly by condensing steam and used these vacuums to extract water from the mines, he called his device 'The Miner's Friend'. Because, as with any vacuum, his device did not actually suck the water up but rather it allowed the atmospheric pressure to force the water up, it could not raise water more than 30ft. This was a serious limitation.
Thomas Newcomen, a contemporary of Isaac Newton, picked up the baton. He used the concept of creating a vacuum by condensing steam in a vertical cylinder and he fitted the cylinder with a piston so that atmospheric pressure would force the piston down. He built his first engine in 1712. In his engine the piston movement was linked through a rocking arm to vertical rods that passed down a shaft into the mine and operated a lift pump. The big breakthrough in Newcomen's design was the use of a water spray into the steam to speed the cooling and the condensation. By operating valves his 'engine' could complete continuous cycles of admitting steam into the cylinder, spraying water, having the piston forced down by the atmospheric pressure, then admitting fresh steam, at about 2psi, at the same time as the weight of the pump rods lifted the piston again. The valves were automatically operated by the movement of the beam so that a significant number of cycles could be completed every minute and, as long as the steam supply could be maintained, it could keep working without tiring.
Here was the real breakthrough. For the first time in the history of mankind they were truly able to harness the energy released in fire to do work. Of course there were big practical problems in building these engines. These engines were large with cylinder diameters of a few feet. There were no machine tools as such. Cylinders were cast and were of limited accuracy, a leather seal around the piston, kept wet with a layer of water on top of the piston, was used to limit steam leakage. The framework of the engine was made of wood, as was the beam. Nonetheless once the capability of these machines was realised there was a big demand for them. Not just for coal mines but for the tin mines in Cornwall, where it is thought the first Newcomen engine was probably built, but the earliest known example of a Newcomen engine was in Dudley. By the time of Newcomen's death in 1729 there were at least 100 of his engines in use. Unfortunately for Newcomen, Savery's patent covered his engine, a rather unjust situation. The methods of manufacture improved with development and by 1775 there were over 600 Newcomen engines in operation and the foundations were laid for the industrial revolution.