“I see a sad procession,
And I hear the sound of coming full-key’d bugles,
All the channels of the city streets they’re flooding,
As with voices and with tears.”
From Dirge for Two Veterans by Walt Whitman: Citizen of the District of Columbia
On the back side of this firebox conversion in Mount Pleasant at Park Road and Mount Pleasant St, NW.
You can see more firebox details here.
Though written about the Civil War, it resonates strongly today.
You can read the full poem here.