Quotes about High-water mark

I believe that any man's life will be filled with constant, unexpected encouragements of this kind (surprises) if he makes up his mind to do his level best each day of his life -- that is, tries to make each day reach as nearly as possible the high-water mark of pure, unselfish, useful living. I pity the man, black or white, who has never experienced the joy and satisfaction that come to one by reason of an effort to assist in making someone else more useful and more happy.