When the difficulty of a problem lies only in finding out what follows from certain fixed premises, mathematical methods furnish invaluable wings for….

An engineer can do for a dollar what any fool can do for two.

To define it rudely but not inaptly, engineering is the art of doing that well with one dollar which any bungler can do with two after a fashion..

Great triumphs of engineering genius-the locomotive, the truss bridge, the steel rail- ... are rather invention than engineering proper..