The “Devil” or the Ericsson Obstruction Remover, as you prefer

Discussing the ironclad attack of April 7, 1863 yesterday, I mentioned the “raft” carried into battle by the USS Weehawken. Drawings of this device often appear with discussions concerning the Confederate maritime torpedoes. It is often cited as the countermeasure for the Confederate weapon.


The raft design came from the genius John Ericsson. The Navy asked him to come up with some means of defeating the obstructions encountered at the entrance to southern harbors, and that would work with the monitors of his design. Ericsson then built a wooden raft that could be lashed to the bow of a monitor. This device was officially named the “Ericsson Obstruction Remover” but often simply known as Ericsson’s Raft. Yankee sailors and Confederates, however, soon named the device “the Devil” due to the ill might offer both friend and foe alike. The navy shipped four rafts to Charleston in the winter of 1863. One was lost in route, leaving three for use in operations.

Four chains secured the raft to the ship. Many references cite the ill-effects on the monitor’s handling when the raft was used. In an official response in regards to the raft prepared weeks after the attack, Captain John Rodgers of the Weehawken indicated the raft imposed no noticeable effects on the monitor’s steering.


Most often reference books will state this was designed to snag Confederate torpedoes to allow them to be pulled from the channels in front of a monitor. The grappling hooks and chains certainly would carry up any such moored devices. But I’ve always had trouble with that simple explanation of the devices’ operations. If the raft snagged a torpedo, and even if then the crew pulled it to the surface by recovering the chains, then what? Hope the control cables broke before the controller on the shore triggered the device? With several hundred pounds of explosive dangling, would the crew scurry out under fire to disarm the torpedo? Just seems a marginal employment if you ask me.

The grapples were not the only feature of Ericsson’s device. A frame on the front of the raft could support two spar torpedoes. That would be, in my opinion, the better option for clearing both obstructions and the nest of torpedoes in a channel. As “support” I’ll offer Rodgers’ report in which he identifies the mode of operation intended for the raft as “for the purpose of carrying a torpedo to be used in blowing up obstructions….

But, before we get too far into that mode of operation, Rodgers refused to mount the torpedoes for the April 7 attack. The thought of working in the tight channel with explosive devices hanging off the bow gave him pause. As things were, Rodgers was the only captain even willing to mount the raft in the first place (and why the Weehawken ended up at the front of the line of battle instead of the USS Passaic commanded by the more senior Captain Percival Drayton).

In action, the raft proved less useful than expected. In fact, as mentioned in the earlier post, at the start of movement the Weehawken‘s chains became fouled in the raft, causing a two hour delay of operations. And while underway the raft caused additional problems:

When inside [the channel], it was found that the sea converted the raft into a huge battering ram, which shook the vessel at every undulation.

It is obvious that with the pitching which always accompanies a swell the two bodies would be brought into collision with a power proportionate to their weight. The raft, I think, displaces about 90 tons of water. Its motions did not at all correspond with [the] motions of the vessel. The raft rose while the vessel fell, and the reverse. It was a source of apprehension lest it should get upon the deck or under the overhang.

As Rodger’s withdrew from action in the afternoon, his engineers noticed several of the armor plates were damaged by the battering of the raft. He then cut the raft loose to avoid additional damage.

The next day Rodgers attempted to use one of the other rafts to destroy the grounded USS Keokuk, using the spar torpedoes. But heavy seas prevented the crew from rigging the raft. The operation was thence canceled (leading to yet another story from the ironclad attack – the salvaging of the Keokuk‘s guns). After April, at least one of the rafts remained with the South Atlantic Blockading Squadron. But the devices fell into even more disfavor. Although trials continued, the officers were reluctant to use them again. Rodgers summed up his experience with the rafts stating, “… no vessel can carry it attached to the bow except in smooth water.”

After Rodgers cast his raft adrift on April 7, it ended up behind Morris Island. There Confederate engineers inspected the raft and provided the detailed sketch seen above. Later the Confederate returned to salvage usable parts from the raft. Captain Francis Lee requisitioned some ten tons of iron fittings from “the Yankee devil” for use in construction of his torpedo rams.

Page 43

What I find remarkable is that the raft used by the Weehawken still exists today. Years ago on an excursion into the waters behind Morris Island in search of the Swamp Angel battery, my battlefield stomping partner mentioned the remains. I was skeptical until we actually tromped out to there to see it. Sadly I didn’t have a camera with me (it was the 1990s and all I had was a cumbersome 35mm). But a recent survey of Civil War related sites around Charleston conducted by the South Carolina Institute of Archeology and Anthropology (SCIAA) for the American Battlefield Protection Program included the “devil.” The survey team visited the raft remains and took wood samples for analysis.

But that is not the only surviving raft. Three years after the Civil War a strange raft drifted close to Bermuda, and was pulled to shore. Later the raft was identified as one of Ericsson’s. The SCIAA report indicates a historian surveyed the remains in 1965.

Oh, but there is another potential Ericsson raft wreck… in Texas! The SCIAA report noted Hurricane Allen in 1980 uncovered remains that also matched the particulars of Ericsson’s design on Mustang Beach, Texas. But from what I gather, there is still some room for debate about the identification of the wreck. I think we need to cue up Andy for a post.



Captain Rodger’s report appears in the Naval ORs, Series I, Volume 14, pages 43-45.

Spirek, James D. The Archeology of Civil War Naval Operations at Charleston Harbor, South Carolina, 1861-1865. prepared by the Maritime Research Division, South Carolina Institute of Archaeology and Anthropology, 2012, pages 118-124. (Accessed online here)

Published by Craig Swain

"Historical marker hunter" and Civil War enthusiast.

10 thoughts on “The “Devil” or the Ericsson Obstruction Remover, as you prefer

  1. I recall hearing about that timbered wreck being discovered after Hurricane Allen, and have seen pictures of it. It was a massively built thing. I’ll ask around and see if anyone has pictures.

    1. Just got off the phone with Tom Oertling, who published an article on this in the International Journal of Nautical Archaeology in 1987 — I’d forgotten about that. He’s going to be sending me some of his stuff. Tom is good people.

  2. Good editorial. A friend of mine found a slave tag while diving in the Cooper River. Did all slaves have these?
    Thanks and God bless you.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: