I did a Yahoo search and found three sites that referred to them as Pook's Turtles. They did resemble turtles. So, I wasn't just dreaming it.
Some further information from the Vicksburg National Park visitors center. The "Turtles" looked so similar, they used color bands on the smokestacks to tell them apart.
Disposition of the vessels:
BARON DE KALB-- sunk after striking a Confederate torpedo (as mines were called) one mile below Yazoo City on July 13, 1863.
CAIRO-- sunk after striking Confederate torpedo in Yazoo River December 12, 1862. Raised December 12, 1964 ( on the anniversary of sinking).
CINCINNATI-- decommissioned and sold. Hull became wharfboat at Gallipolis, Ohio. Engines used in tug QUAKER.
LOUISVILLE-- decommissioned and sold
PITTSBURG-- Sold and abandoned in 1870
MOUND CITY-- decommissioned and broken up 1866
One of the heavier losses in the naval war occurred on board the Mound City when a shell pierced and exploded in the steam drum June 1862 and killed or injured 150 crewmembers.
A Pook in a Turtle or Is That a Turtle in a Pook. --Old B-Runner
The Battle of Fort Fisher, N.C.
