Dave Bonta's "Day of mourning" is a single sentence, and it gets its weight from one odd, quiet image. The bells ring all day long, which gives us a picture of grief that is public, loud and unending. Then the last line shrinks everything down: "one ration of sorrow." A ration is a measured, limited portion, the kind you get in wartime or hardship. So the sorrow here is oddly small and controlled, even while the bells go on and on.
That clash is what makes the poem work. The speaker seems to feel a kind of numb, tired grief. The bells keep announcing mourning, but the person hearing them has only so much feeling to give, and it has to be stretched across the whole day. You could also read it as a hint that grief is something shared out, and that there is never quite enough to go around. The mood is hushed and heavy, with a hint of exhaustion, as if the ringing has outlasted the feeling it was meant to express.