✔ 最佳答案
Oil and Global Warming We tend to see urban pollution as a modern problem. But did you know that urban pollution was a serious problem for Western world cities as far back as 200 years ago? The greatest source of pollution for 19th-century cities was, believe it or not, the horse. Horses were ubiquitous back then. They drew pretty much anything that was heavy and had to move. Horse-drawn carriages, trains, wagons, supply carts…you name it. Of course, there were no horse toilets, so these animals had to relieve themselves in the streets. This might seem like a quaint issue until one realises that the average city horse could produce up to 35 pounds of manure and 2 pints of urine a day. Yuck! » Source: Daily Reckoning Today, we have to deal with global warming and Peak Oil – back then, they were dealing with global stench and peak manure. It truly was a serious problem. And they couldn’t keep up with it, because the cities were growing rapidly. So the conventional thinkers of the day had no problem breaking out their 19th-century spreadsheets and calculating that at the rate the population was increasing, everyone would soon be up to their knees in dung. Again, a serious problem! With the benefit of hindsight, we know how the problem was solved. But think about the solution for a moment. The horse pollution problem was not solved through tinkering with the current system. Nobody put nappies on the horses. Nobody figured out how to vaporise the manure. Nobody figured out how to make the stench disappear. Nor was the problem solved through political intervention.