Extremely well-researched if rather dry snapshot of the state of energy resources and research at time of writing. That time happens to be the 1970s, so this is clearly not applicable to today's energy issues but it's nonetheless an interesting snapshot of the period. Foley is primarily concerned, I think, with establishing a need for energy conservation and adequate planning for future use. That's a recommendation that still holds value today, given our continued reliance on oil and other fossil fuels. One interesting fact that I never knew: apparently back in 1273, London had an anti-pollution law that banned coal-burning in the city. One can only wonder what those law-makers would make of coal today!