Too late I stayed,—forgive the crime!
Unheeded flew the hours;
How noiseless falls the foot of time
That only treads on flowers.
Lines to Lady A. Hamilton, reported in Bartlett's Familiar Quotations, 10th ed. (1919). Compare: "The inaudible and noiseless foot of Time", William Shakespeare, All's Well that Ends Well, Act v. Scene 3.