My heart is a bone. I chew it for an hour every day. I heard once that humans have muscle hearts but I didn't believe it then and I don't believe it now. Heart marrow is why I'm warm blooded but it's inches between here and there. When my heart pounds it's a drum I beat to tell myself these rhythms repeat. I woke up this morning and checked my heart bone; I have been grinding it in the night and the dentist says I need to guard my heart's jaws or my teeth won't grip the next time I put it in my mouth.