(group) The United States used wood in metallurgy long after the British had changed to coal. Was this evidence of technological backwardness in the United States? If the United States was technologically backward, how would you explain the fact that all sorts of machines for woodworking were perfected in the United States in the first half of the nineteenth century? Fireplaces are often said to be inefficient ways to heat a room. Why then were they so widely used in the United States in preference to stoves? (Hint: larger logs can be used in fireplaces.) Why did stoves become more popular as wood prices increased?
It depends on what one means by technologically backward. A population could use a technologically backward method because it is more economically efficient. Fireplaces are an technologically inefficient way to heat a room. More energy goes toward ends other than heating the room than with other means. However, it is economically efficient. Otherwise, the individuals who picked that method of heating would have chosen differently.
Again, I don't suppose this is the answer for which the author is looking. Reasoning being that the author spends a bunch of the beginning of the chapter telling us how the scientific definition of efficiency means nothing and is a worthless concept. We should use only an economic definition according to him. I suspect he views this problem similarly.