So there’s no need for Daniel to make some foolish pretense of seeing this venture through the shrewd eyes of a businessman. He tries, rather, to see it as what he is: a Natural Philosopher. As such it is the experimental aspects of it—its failures—that draw his notice. The level ground below the Engine is pocked, all around, with wreckage of Newcomen’s boilers. The natural and correct form for such a thing is a sphere. Knowing as much, Newcomen has been learning how to fabricate large spherical shells out of iron. And just as a schoolboy’s waste-book is littered, page after page, with smeared and scratched-out failures, so the deep soil of the river-bottom is strewn with ineradicable records of every idea that Newcomen has ever had on the subject, and striking visual proof of why and how certain of those ideas were bad. He can’t possibly beat out a single billet of iron into a vast seamless bubble and so he has to piece the things together of many smaller curved plates, lapped and riveted.