Transcribed below. The typewriter is an Underwood Standard Portable that is 99 years old this year.

Apologia pro versificatione sua.

A century is far too short a time
To reach the airy heights of the sublime.
Millennia would hardly be enough:
The laughing eons love to call our bluff.
   So pardon me if this my rhyme
      May seem a little rough.
      I simply haven’t time
   To think of any better stuff.