In my intercourse with mankind, I have always found those who would thrust theory into practical matters to be, at bottom, men of no judgement and pure quacks.

It is contrary to the usual practice of professional men to give their opinions upon each other's work unless regularly called upon in the way of their profession.

Stone, wood and iron are wrought and put together by mechanical methods, but the greatest work is to keep right the animal part of the machinery.

The history of men of science has one peculiar advantage, as it shows the importance of little things in producing great results. Smeaton learned his principle of constructing a lighthouse, by noticing the trunk of a tree to be diminished from a curve to a cyclinder ... and Newton, turning an old box into a water-clock, or the yard of a house into a sundial, are examples of those habits of patient observation which scientific biography attractively recommends.

...learning chiefly in mathematical sciences can so swallow up and fix one's thought, as to possess it entirely for some time; but when that amusement is over, nature will return, and be where it was, being rather diverted than overcome by such speculations.