A mystery poem. It is often attributed to G.W. Langford. Although it's hard to trace down where it first appeared, all known copies printed in England before 1900 attributed it to either Langford or 'anonymous'. Langford family tradition has it that it was written by G.W. Langford while he was visiting his birthplace in Ireland in 1845. The earliest known publication of the poem in England was in 1848.
But in America... In 1986 a copy of the Philadelphia Inquirer from July 15, 1845 was discovered with Speak Gently printed on page two -- and signed with the initials D.B. A later work by David Bates, The Eolian, 1849, also includes the poem, and Bates' son confirms that his father wrote it.
While we don't really know who wrote the poem, currently most people seem to be favoring the D. Bates theory. I personally am happy with anonymous.
You probably know this poem only indirectly, through its parody Speak roughly to your little boy, appearing in Lewis Carroll's Alice's Adventures in Wonderland.
Speak gently! It is better far
To rule by love than fear;
Speak gently; let no harsh words mar
The good we might do here!
Speak gently! Love doth whisper low
The vows that true hearts bind;
And gently Friendship's accents flow;
Affection's voice is kind.
Speak gently to the little child!
Its love be sure to gain;
Teach it in accents soft and mild;
It may not long remain.
Speak gently to the young, for they
Will have enough to bear;
Pass through this life as best they may,
'Tis full of anxious care!
Speak gently to the aged one,
Grieve not the care-worn heart;
Whose sands of life are nearly run,
Let such in peace depart!
Speak gently, kindly, to the poor;
Let no harsh tone be heard;
They have enough they must endure,
Without an unkind word!
Speak gently to the erring; know
They may have toiled in vain;
Perchance unkindness made them so;
Oh, win them back again!
Speak gently! He who gave his life
To bend man's stubborn will,
When elements were in fierce strife,
Said to them, "Peace, be still."
Speak gently! 'tis a little thing
Dropped in the heart's deep well;
The good, the joy, that it may bring,
Eternity shall tell.