Nature is our kindest friend and best critic in experimental science if we only allow her intimations to fall unbiased on our minds.

What a weak, credulous, incredulous, unbelieving, superstitious, bold, frightened, what a ridiculous world ours is, as far as concerns the mind of man. How full of inconsistencies, contradictions and absurdities it is. I declare that taking the average of many minds that have recently come before me ... I should prefer the obedience, affections and instinct of a dog before it.

I ... express a wish that you may, in your generation, be fit to compare to a candle; that you may, like it, shine as lights to those about you; that, in all your actions, you may justify the beauty of the taper by making your deeds honourable and effectual in the discharge of your duty to your fellow-men.

A man in twenty-four hours converts as much as seven ounces of carbon into carbonic acid; a milch cow will convert seventy ounces, and a horse seventy-nine ounces, solely by the act of respiration. That is, the horse in twenty-four hours burns seventy-nine ounces of charcoal, or carbon, in his organs of respiration to supply his natural warmth in that time ..., not in a free state, but in a state of combination.

ou can hardly imagine how I am struggling to exert my poetical ideas just now for the discovery of analogies and remote figures respecting the earth, sun, and all sorts of things — for I think that is the true way (corrected by judgment) to work out a discovery.

The book of nature which we have to read is written by the finger of God.

What a delight it is to think that you are quietly & philosophically at work in the pursuit of science... rather than fighting amongst the crowd of black passions & motives that seem now a days to urge men every where into action. What incredible scenes every where, what unworthy motives ruled for the moment, under high sounding phrases and at the last what disgusting revolutions.