One day is there of the series

One Day is there of the series
Termed "Thanksgiving Day"
Celebrated part at table
Part in memory -
Neither Ancestor nor Urchin
I review the Play -
Seems it to my Hooded thinking
Reflex Holiday -

Had There been no sharp subtraction
From the early Sum -
Not an Acre or a Caption
Where was once a Room
Not a mention whose small Pebble
Wrinkled any Sea,
Unto such, were such Assembly
'Twere "Thanksgiving Day" -