Lecture 18 - Industrial Revolution or Evolution?

The following is a flow-chart or outline of the foundation and origins for the Industrial Revolution:

Beginning in the AD 1400's...

Increasing population: in contrast to the mass-deaths caused by the Black Plague in the AD 1300's.

Deforestation and erosion throughout Europe. Wood was the main fuel for cooking and heating. Plus, forests had to be cleared for expanding agriculture.

Charcoal: Deforestation is further exacerbated by reducing trees to charcoal, which burns cleaner and hotter.

Blast Furnaces (cast iron): In AD 1463, water-wheel-powered bellows permit the casting of iron (1,400 C) in Europe by using blast furnaces.

Increased Deforestation: The increased supply generates an increased demand for iron which, in turn, demands many more trees. In Britain, with lots of iron supplies, this is particularly important because the iron industry is soon competing for wood resources with the Government, particularly the Royal Navy.

Royal Navy cuts off supply of wood: The construction and maintenance of top-quality warships, such as the Royal Navy required, demanded thousands of trees...trees which the charcoal-makers were burning at an alarming rate. Thus, as early as AD 1558, the government greatly restricted the use of wood for iron-making.

Demand for coal increases: The shortage, and resulting high cost, of wood for all purposes meant that alternative sources of energy were explored. Coal, which Britain had huge supplies of, was increasingly used in many areas where wood had been burned before. However, the impurities in coal meant that iron smelted and cast in a coal-fired furnace was weaker and more-brittle than iron produced in charcoal-fired furnaces.

Coke used for iron smelting: In AD 1709, Darby, using technology borrowed from beer-brewers, finds that iron produced from furnaces burning pre-heated coal was as strong as iron produced in furnaces burning charcoal. Thus, the deforestation-induced energy-crisis was resolved. (Here's a good SAT question for you: Coke is to coal as charcoal is to _______. Answer: Wood). Darby set up shop in Coalbrookdale whose furnaces color the cover of your textbook.

Deeper Mines: The increased demand for coal, exacerbated by the new demands from the iron industry, means that deeper and deeper deposits must be mined.

Problems with Mine Flooding: The Earth contains A LOT of water beneath its surface. The mountains around us (Nittany, Tussey, etc.), even though they are above us, contain A LOT of water (That is why we can see Penn's Cave by boat). Of course, as mines go deeper, they have more problems with water filling the tunnels (particularly in Britain where the sea is never that far away). Thus, as the illustrations in De Re Metallica(see Lecture 15) show, miners have always had a need for efficient methods to pump water. This was magnified by the increasing demands for deep coal in the 16 and early 1700's.

Atmospheric Engine Invented: In AD 1712, Newcomen, building on the observations of scientists in the 1600's, built the first machine that transformed chemical energy into mechanical energy (until then, all other sources obtained power from either muscles or natural energy from wind and water). Basic physics: Steam (hot water-vapor) occupies more space than an equivalent mass of water. Newcomen's machine, while not quite a genuine steam engine, used vacuum formed by condensing steam to pull a piston which, in turn, operated a pump. Needless to say, the pump was in a mine-shaft! This had two major results:

1.) More Coal: First, because deeper mines were finally possible, a lot more coal became available.

More Iron: Because coal was cheaper, iron became cheaper and more commonly used...for things like atmospheric engines!

Increased demand for Coal: With all the blast-furnaces and boilers, even more coal was needed!

Increased need for Transport: With all this coal and cheap iron goods that needed to be distributed, improved methods of moving large, heavy loads over long distances became necessary. The result was:

Canals: The first one opened in AD 1757: permitted coal to be transported hundreds of miles from the mines to the blast furnaces at low cost.

2.) Steam Engine: Newcomen's atmospheric engine began another major trend. While it was an unprecedented invention, Newcomen's engine was very inefficient: it used a lot of coal for the amount of work it did because it relied on atmospheric pressure and gravity to actually move the piston. Thus, only coal mines could really afford to use them. Only after it was improved by Watt, and later Trevethic, could it actually be called a "steam engine". In their designs, it was the pressure of the steam, itself, that moved the piston thus making it much more powerful and efficient. Thus, a cheap, and versatile source of power was available to industry by the beginning of the 1800's. It is the use of this invention that marks the beginning of the Industrial Revolution.

Railroads: Portable steam engines 1820's

Easier long-distance travel: for the first time, people didn't have to live and die within 7 miles of their place of birth.

Migration: people moved to cities, but still lived in poverty.

Iron Construction: As demonstrated by the iron bridge in Coalbrookdale in 1781, techniques to manipulate iron on a very large scale were being developed.

Steamships: Construction of the Great Britain in 1845 combined construction with the steam engine.

Migration to America: Cheap trans-Atlantic transport enabled people to flee poverty by moving to America.
 Flow chart of events in chapters 7 and 8