Lumps in powders, but not all.

Untitled Poem

The ways of powders have me stumped.
My powdered milk will cake and clump;
  My salt will clump as well.
I sometimes find a pepper ball;
Of sugar, cheese, and others all
  I’ve lumpy tales to tell.
Yes cinnamon, however old
Though dry or wet, though hot or cold
Will never other granules hold
  But as a powder dwell.