right. For the finger of God is surely the compelling power of the laws of Nature, and the erection of such a structure is made possible only by the accurate calculation of theforces acting upon each member of the bridge in accordance with those laws; a computation that no man could make from the knowledge won by his own experience alone.
There are some branches of Engineering, such as Electrical Engineering, that have obviously been almost entirely dependent for their advancement upon scientific investigation, but there are no branches that can progress without it. James Watt, who was trained as a maker of scientific instruments, showed keen appreciation of this fact when he completed his inventions relating' to the steam engine by the invention of the indicator. This is the scientific tool that enables the performances of engines to be weighed and measured, and the progress of both steam and gas engine since Watt's time has been largely due to its use. Indeed such progress would have been impossible without it. Yet a recent editorial in "Engineering" lamented the fact that even now some British makers of engines will persist in acting as though the indicator did not exist, with results very harmful to British trade. The relation of the indicator to the steam engine typifies that between scientific method and engineering generally. It is everywhere the active agent that stimulates progress. Even in branches of Engineering commonly regarded as purely practical arts, such as road engineering, experience, has shown that the most successful engineers are those who apply to the practical problems minds having knowledge of related sciences and trained in scientific method, and in several American Universities special Degree courses are now given for Road Engineers. Every branch of Engineering has the same story to tell. You all know what a vital force was scientific engineering in the great war. The Germans had the first advantage, largely because for a
