This would be a far better book if Gimpel didn't have Oswald Spengler on the brain. As things stand it's an eccentric combination of medieval technology and dire warnings on the coming collapse of the decadent West. (Did you know that the Lever House building in New York, constructed in 1953, signaled the beginning of the end for American economic expansion?) ""Dynamism"" is French historian Gimpel's favorite concept and he is out to redress the popular view of the Middle Ages as a ""scholastic and static"" society. Because the history of technology and engineering for the most part remains to be written, Gimpel makes some headway--though it won't come as news to historians that the 11th through the 13th centuries were a period of population growth, improved agricultural yields, a thriving textile industry in Flanders, and nonpareil architectural achievements. When examining the vast extent of medieval stone quarrying and metallurgy, the spread of Cisterian ""factories"" or the labor conditions among masons, weavers, and miners, Gimpel is stimulating and provocative. The ""grevous compleynt"" made by townsmen against water and air pollution is an equally arresting topic. But to speak of the ""breaking down"" of medieval hygiene after the 13th century is to assume standards of cleanliness that never existed. And, while the great architect-engineers who built the medieval cathedrals may have been ""heroes,"" the conclusion that medieval men prized invention and innovation per se and were constantly on the lookout for new sources of power beyond wind and water is characteristically extreme. A tendentious and maddening book.