Lectures which really teach will never be popular; lectures which are popular will never really teach.

It is right that we should stand by and act on our principles; but not right to hold them in obstinate blindness, or retain them when proved to be erroneous.

I cannot conceive curved lines of force without the conditions of a physical existence in that intermediate space.

I happen to have discovered a direct relation between magnetism and light, also electricity and light, and the field it opens is so large and I think rich.

Since peace is alone the gift of God, and as it is He who gives it, why should we be afraid? His unspeakable gift in His beloved Son is the ground of no doubtful hope.

Physicist is both to my mouth and ears so awkward that I think I shall never use it. The equivalent of three separate sounds of "I" in one word is too much.

The lecturer should give the audience full reason to believe that all his powers have been exerted for their pleasure and instruction.