THE EOYAL AETILLEEY INSTITUTION. 
451 
“ But the monitors, for harbour defence, are just as valuable as they were on the 
day when the first one drove the leviathan ‘ Merrimack 5 back to her hole, and 
saved the honor of the nation. I am sure that monitors would have done much 
better on this river than the old Pook gunboats did, which were built for temporary 
purposes only, or until monitors could take their places. Earthworks on elevated 
positions are difficult to silence, it is true, except by a concentrated fire of many 
guns, and monitors are not well provided in numbers. No vessels have been more 
successful than the Mississipi gunboats, whenever they have been called on to 
attack such works. Still they were very deficient in one respect, as they were 
very vulnerable, suffered a good deal, and proved that in the end the monitor 
principle, from its invulnerability, was the only thing that could be safely depended 
on. Eor this reason I often wished that I had been provided with one good 
monitor, with which, at certain times, I could have accomplished more than with a 
fleet of such boats as we have here. 
“ A new boat, the * Ozark,’ has just arrived here. As far as her turret is con¬ 
cerned she is all right, but her hull is too high out of water, and she lacks 
more than three inches of iron on fifteen inches of oak. I have, moreover, noticed 
that where there is a backing of wood covered with three-inch iron, and that iron 
with wood again, the resistance of the latter will prevent balls of heavy size from 
entering the iron. In fact, it is hardly indented. This was particularly demon¬ 
strated in the passage of the fleet past Vicksburg, when it was necessary to take 
every precaution to insure success and prevent injury to the steamers. Heavy logs, 
twenty inches in diameter, were hung perpendicularly on the sides of the vessel, 
close together, and so secured that no shot could strike the side without passing 
through the logs. Bales of hay were also packed over the decks and stems in 
sufficient thickness (it was supposed) to prevent the passage of any shot. Suffice 
it to say, the pressed hay was no protection whatever against shot or shell. They 
passed through four or five bales, and very much endangered the vessels by setting 
the hay on fire. Wherever the projectiles of the enemy struck the logs, they did no 
further damage; they would pass through the logs, strike the iron without leaving 
more than an indentation, and glance off. Many instances of narrow escapes could 
be mentioned, where the vessels were saved by the intervention of the wood, and 
in no instance were the vessels damaged where the logs were properly placed. 
The incidents of that night—the passing of the Vicksburg batteries—suggested to 
me the idea of first having a heavy backing of wood, then a layer of iron, and then 
a covering of wood over the iron, which will, I am convinced, make a vessel 
perfectly shot-proof..There are two vessels in this squadron, the ‘ Lafayette ’ 
and e Choctaw,’ which give proof of the value of heavy backing to iron. These 
vessels were built with heavy frames, covered on the outside with gutta-percha, and 
then with a light thickness of iron. Whenever these vessels have been struck on 
the iron where the wood backing was heavy, they resisted the shot of heaviest 
calibre, but where the backing was light shot went in at one side and out at the 
other. The defence of gutta-percha was not of the slightest use; on the con¬ 
trary, it was a detriment, and aided very much in destroying the vessels by rot. 
“ As to approving of any of the above-mentioned styles of gunboat, as part of a 
permanent system of national defence to be adopted in this country, that I cannot 
do. Any professional man who will lay aside his prejudices caused by the dis¬ 
comforts incident to the monitors, must admit that, as a harbour defence, they are 
the best and only vessels to be built; and I hope we shall see every harbour in the 
United States, where there is a chance of an enemy penetrating, supplied with two 
or three of these floating batteries. If they have not been able to penetrate the 
harbour of Charleston, where fifty guns to one was opposed to them, and where 
they had to contend with obstructions placed in their way impossible to be removed, 
it in no way detracts from their well-earned reputation for efficiency. They have 
[vol. iv.] 59 
