Smil 4, part 2

technological progress in transportation and construction before steam engines was real, but irregular
technology did not steadily progress

technological progress depends on what is driving it

• laziness--make your work easier
  
• seeking religious benefits
• trade for materials and goods that can't be produced locally
  
• capitalism (free market)--the opportunity to improve your life by making more money
• political power
• between countries (political and military)
• demonstrate your power to your own people so they don't rebel
  

road building was probably more important than using animals efficiently
 the Chinese road system was similar to the Roman one but not quite as extensive or overbuild as Roman roads
 the Incas also build an impressive road system
why roads? power, either military or for trade

water transport was much cheaper than land

• rivers flow irregularly and have hazards--canals are the most efficient
• key problem is technologies to change levels, first slipways, then locks
• boats in canals were often towed by animals walking on a tow path beside the canal
  
• Europeans copied Chinese technology in the 16th century

sailing ships are useful mostly in oceans

• oared ships were useful for warfare but took a great deal of human energy (and suffering)
  
• square sails are useful mostly if the wind is behind you, triangular sails allow zigzagging towards the wind
• weaving the sails was a major expense

buildings

• large monuments like pyramids depend most on labor supply
• cathedrals were more sophisticated engineering
• Roman aqueducts were particularly bold engineering, requiring exact slopes
• large buildings were a display of power and legitimacy
  

metal:

• crushing the ore is the first labor-intensive step
  
• charcoal was key for smelting metal
  
• bronze was first widely used, but copper to make bronze is much rarer and therefore more expensive than iron
  
• smelting iron requires much higher temperatures so a forced air supply and huge amounts of charcoal
• in the simpler technologies the iron is not actually melted, just softened and hammers, which can also be used to shape it and even to control the amount of carbon
  
• Chinese were first to melt and cast iron

warfare:

• catapults and trebuchets
• mounted soldiers (cavalry) depended on the stirrup
• gunpowder invented in China first for fireworks and then fire lances
• developed into cannon
  
• but Europe was quickly catching up, first with bronze cannon with stone cannonballs, then with cast iron cannonballs and then cannon
• led to the development of much stronger earthworks and other defenses
• a cannon safe enough to mount on a ship made a particular difference in warfare