When the mind once allows a doubt to gain entrance, the value of deeds performed grow less, their character changes, we forget the past and dread the future.

Though sleep is called our best friend, it is a friend who often keeps us waiting!

A scholar has to know a little of everything.

But to find, all at once, right before your eyes, that the impossible had been mysteriously achieved by man himself: this staggers the mind!

While there is life there is hope. I beg to assert...that as long as a man's heart beats, as long as a man's flesh quivers, I do not allow that a being gifted with thought and will can allow himself to despair.

As for difficulties," replied Ferguson, in a serious tone, "they were made to be overcome.

What a big book, captain, might be made with all that is known!" "And what a much bigger book still with all that is not known!