This week's Dauphin Island history post is a portion of an 1822 U.S. House of Representatives' Committee on Military Affairs' investigation into the potential fortification of Mobile Bay and the map which was used to make their conclusion which was that THERE WAS NO JUSTIFICATION FOR FORTIFYING DAUPHIN ISLAND.

The map in this post is not the original one used by the Congress in 1822 but it is based up the original drawn by Mobilian Curtis Lewis in 1820. The posted map was published in 1896 by Alabama native, William Trent Rossell.

Not only did Curtis Lewis map Mobile Bay in 1820 but he also had some other strong ties to Dauphin Island. His wife was the granddaughter of Major Robert Farmar, namesake for D.I.'s Major Farmar Street. At the time Lewis produced his map, his wife's family's estate had filed a private claim with the United States for ownership of Dauphin Island based upon a deed obtained by Major Farmar in the 1760s. Lewis' father-in-law, Louis de Vaubercey, who married Farmar's 2nd child, Mary Elizabeth http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GRid=12835704, established a lime kiln on D.I. in the early 19th century using the Indian shell mounds as raw material to produce mortar. Vaubercey died on Dauphin Island on April 10, 1837.


https://books.google.com/books?id=Y5YbAQAAMAAJ&pg=PA345&lpg=PA345&dq=%22mobile+bay%22+%22military+affairs%22+february+28,+1822&source=bl&ots=A87EJGfmmJ&sig=LXq5ZsjjvTJe2zaH3Y93xIgF2hY&hl=en&sa=X&ved=0ahUKEwjk_6e9qMPNAhXHeCYKHfTRCKcQ6AEIJDAB#v=onepage&q=%22mobile%20bay%22%20%22military%20affairs%22%20february%2028%2C%201822&f=false

 https://books.google.com/books?id=Y5YbAQAAMAAJ&pg=PA388&lpg=PA388&dq=%22curtis+lewis%22+%22mobile+bay%22+eustis+%22house+of+representatives%22&source=bl&ots=A87EJGejoE&sig=0OZQX8t5hUcMSdkP8rAzuB8nvDc&hl=en&sa=X&ved=0ahUKEwiS1O_Yo8PNAhVBPiYKHcO5C84Q6AEIHjAA#v=onepage&q=%22curtis%20lewis%22%20%22mobile%20bay%22%20eustis%20%22house%20of%20representatives%22&f=false

 "The report of the engineers states that the object of forts on Mobile Point, and on the eastern point of Dauphin Island, is to prevent the enemy from occupying them as places of refuge, to prevent the mouths of the river from being blockaded, to secure the communication between New Orleans and Mobile Bay.

The fort on Dauphin Island is intended to defend the western channel, which they state to be one mile distant, and having a depth of water of ten feet according to their chart, and seven feet according to Lewis, through which vessels constructed for the purpose, and drawing from eight to nine feet water, and mounting twelve or fifteen guns, might enter the bay. It will also, they add, deprive the enemy's vessels of the anchorage under Pelican Island, which anchorage they state to be fit for vessels drawing seventeen or eighteen feet water — that is to say, sloops of war. It will also, as they say, prevent an enemy from establishing himself on Dauphin Island, by cutting a communication between Lake Pontchartrain and Mobile Bay, while the fort will serve as a depot for naval stores, and for the stores and armament necessary for the protection of the coasting trade.

The committee have given these subjects due consideration, and have also considered Dauphin Island in all its bearings and relations, and cannot believe them of sufficient importance to justify an expenditure of a million of dollars, which the work on Dauphin Island, with its ordnance and necessary fixtures, will probably require, without taking into view the subsequent expenses incident thereto.

Would a fort on Dauphin Island effect the object contemplated by the engineers? The committee conceive that it could not. It is too far distant from the ship channel to aid in preventing a blockade; nor can the fort on Mobile Point, although near to the channel, entirely effect it. A single sloop of war lying at anchor within the bar, three miles distant from the fort, or in the bay, out of gunshot of the fort, would effectually blockade the bay with out being exposed to danger from either fort.

Will a fort on Dauphin Island protect the coasting trade from New Orleans? Certainly it cannot. The channel for coasting vessels has from four to five feet water, and is at least four miles distant from the site of the fort on Dauphin Island. The coasting trade cannot, of course, receive protection from any force placed there.

Would a fort on Dauphin Island be able to deprive an enemy of anchorage under Pelican Island? A sloop of war might anchor under that island, if the engineers' chart be correct, and might remain there. She would then be thirty-five miles distant from Mobile, and could approach no nearer; for the western channel has only ten feet water according to the engineers' chart, and but seven according to Lewis's. The chart last mentioned, and that from the Navy Office, give only eleven and twelve feet water to the entrance; to the anchorage under Pelican Island, of course, not even a sloop of war can enter, if these charts be correct. It is alleged that vessels drawing eight or nine feet water, and mounting ten or twelve guns, may pass through the western channel. If Lewis's chart be correct, they cannot; if that of the engineers be correct, they may. Such vessels may, however, pass more conveniently in the night, in the ship channel, in deep water, and make their arrangements at their leisure for an attack on the city of Mobile or Blakely in the bay, and out of gunshot of the fort.

The engineers say 'that the western channel being one mile from the site of the fort on Dauphin Island, such vessels would pass with very little annoyance from the shot of the fort, and that they can be prevented in no way but by a floating force;' from whence it follows that the immense fortification contemplated on this island could not have the effect of preventing such vessels from entering the bay. The anchorage under Pelican Island may be entered, agreeably to the engineers' chart, by vessels drawing 17 or 18 feet water; but according to the chart of the Navy Commissioners, and that of Lewis taken in 1820, there are only 11 or 12 feet of water; and if these be correct, even sloops of war cannot enter. Vessels drawing only 8 or 9 feet water, and mounting 12 or 15 guns, must, as your committee apprehend, be built for the occasion. The steam frigate and gun-boats herein recommended would, in the opinion of the committee, prove a more effectual security against an enemy entering the bay than the 108 guns proposed to be mounted on the land.

The objection to the occupation of Dauphin Island by an enemy, and to his making an establishment there, from whence to cut off the coasting trade between New Orleans and Mobile, consists in this: the water is not sufficiently deep for him to be protected by his fleet, while his object may be much better accomplished by taking possession of Cat Island, thirty miles distant from Lake Pontchartrain, and about fifty miles from the east end of Dauphin Island, where large ships of war may lie in safety, and from whence he may completely intercept their (trade. A single sloop of war stationed at Cat or Ship Island would destroy their trade, without risk, unless prevented by a superior naval force.

The fort on Dauphin Island cannot be made use of as a depot of naval stores, or armament for defense of the coasting trade, because the depth of water for nearly a mile distant from the shore will not admit our smallest vessels. Should such a place of deposit be deemed necessary, Mobile Point is in every respect preferable. The harbor near the Point is good, and the water sufficiently deep for vessels to anchor near it, and to discharge their cargoes with facility.

From the best view which the committee have been able to take of the subject, it appears to them that the fortification on Dauphin Island, calculated to contain 108 guns, ought to be discontinued; that an enclosed work on Mobile Point, calculated to mount fifty or sixty pieces of heavy ordnance, with an adequate floating force, and twenty or thirty pieces (say twelve, eighteen, and twenty-four pounders) mounted and deposited in an arsenal to be erected for that purpose at Mobile or Blakely, from whence they may be detached, as occasion might require, to the points of land by which the boats or barges of an enemy must necessarily pass in his approach to either of those places, and to cover the floating force in case of retreat, would constitute a suitable defense for the bay of Mobile.

 All which is respectfully submitted.

Statement of distances— Dauphin Island.

Distance from Dauphin Island to Mobile Point,
           On the large map, - - - - - - - -3 miles.
           On engineers' chart, - - - - - - - 3 and one third miles
           On Lewis's marine chart, - - - - - - -4 miles

Distance from the same to the ship channel,
           On large map, - - - - - - - -2 and one half miles
           On engineers' chart, - - - - - - - - 2 and one half miles
           On Lewis's chart, - - - - - - - - 2 and one half miles

Distance from the fort on Dauphin Island to Pelican Island,
           On large map, (not given.)
           On engineers' chart, - - - - - - - -2 and one quarter miles
           On Lewis's chart, - - - - - - - - 4 miles

Distance from fort on Dauphin Island to Passe au Heron, or coasting channel,
          On large map, - - - - - - - - 3 and one quarter miles
          On engineers' chart, - - - - - - - 3 and one half miles
          On Lewis's chart, - - - - - - - -7 miles

Depth of water on the bar,
          Large chart, - - - - - - - -18 feet.
         Engineers' chart, - - - - - - - -18 feet
         Lewis's chart, - - - - - - - -16 feet

Channel near Dauphin Island,
         Large chart, - - - - - - - -12 feet
         Engineers', - - - - - - - -10 feet
         Lewis's, 12 feet, with a pass of only - - . - - - - 7 feet

Entrance to get under Pelican Island,
         Large chart, - - - - - - - -12 feet
         Engineers', - - - - - - - -18 feet
         Lewis's, - - - - - - - - -11 feet

Passe au Heron, or coasting channel,
         Large chart, - - - - - - - -5 feet
         Engineers' not given.
         Lewis's, - - - - - - - - -4 feet

Distance from Mobile Point to the city of Mobile, in a straight line,
        Large chart, - - - - - - - -35 miles.
        Lewis's, - -'- - - - - - -33 miles

Distance from 18 feet water to the city,
        Large chart, - - - - - - - -28 miles
        Lewis's, - - -, - - - - -26 miles

Distance from 14 feet water,
        Large chart, - - - - - - - -15 miles
        Lewis's, - - -' - - - - - - 13 and one half miles

Distance from 10 feet water,
        Large chart, - - - .- - - - -3 and one half miles
        Lewis's, - - - - - - - - -6 miles
        Depth of water, - - - - - - 7 feet.

Pass or channel from the anchorage under Pelican Island to the ship channel, - - - 9 feet.

Pass or channel from the same, to proceed direct to the city of Mobile, - - - 7 feet

Distance from Ship Island to the main, Large chart, - - - - - - - -6 miles.

From Cat river, - - - - - - - 7 and one half miles

Depth of water near those islands, - - - - - - 21 to 24 feet.

Distance from 18 feet water, near Cat Island,

To Bienvenue, - - - - - - - -35 miles.

From same to the pass Rigolets, - - - - - - 20 miles

Distance from Dauphin Island to the Rigolets - - - - - - 9
                                                                                                                    Washington, April 8, 1820.
Colonel:

I have the honor of submitting to you, as you require, the motives which determined the board to propose occupying the eastern point of Dauphin Island by a fort of the same importance and dimensions as that which has been projected at Mobile Point.

In the report presented by the board (1818) on the defense of the frontier of the Union, on the Gulf of Mexico, the following considerations are those which determined us to defend the entrance of Mobile Bay: 1st, To prevent the enemy from occupying it as a port of refuge, from whence he might act against the other parts of the frontier; (a consideration which would become of still greater importance, if, in consequence of the acquisition of Florida, Pensacola became a naval depot and harbor of rendezvous.) 2d, To prevent the mouths of the navigable rivers which fall into this bay from being blockaded, which in time of war would cut off the State of Alabama (and all the new States to be formed hereafter on that frontier) from all communication with the ocean; and, when on this subject, we shall observe that the communication between the Tennessee and the ocean will hereafter take place through Mobile Bay by artificial canals. 3d, To secure the communication between New Orleans and Mobile bay by Lake Pontchartrain, and the little interior sea comprised between the main and the chain of islands bounded by Cat Island to the west, and Dauphin Island to the east.

Upon these principles we must conclude that it is not sufficient to close the entrance into Mobile bay, but that we must prevent it from being blockaded, as well as localities will allow.

The entrance into the bay between Dauphin Island and Mobile Point is from three to three and a half miles wide, and has two channels of entry. The eastern and principal channel is one mile wide opposite Mobile Point, and is crossed, three miles below, and to the south of it, by a bar which has only from seventeen to eighteen feet of water at full tide. The western channel passes at one thousand two hundred yards' distance from the eastern point of Dauphin Island; its breadth is about three hundred yards, and it is about ten feet deep; the eastern or farther side of this channel is thus at the same distance (one mile) from Dauphin Island as the western or further side of the main channel is from Mobile Point. This breadth (one mile) is rather too great to be very effectually or strongly defended by land batteries above; the board have, therefore, recommended, in time of war, to defend these channels by a division of gun-boats acting in concert with the forts supported by and supporting them.

The first object of the fort projected on the eastern point of Dauphin Island is thus to batter the western channel, where vessels constructed for that purpose, drawing from eight to nine feet of water, and carrying from twelve to fifteen guns, might penetrate into the bay. But it also satisfies to many other important conditions. 1st. It will deprive the enemy of the anchorage north of Pelican Island, and three hundred yards south of Dauphin Island, and secure it to the navy of the Union. This anchorage is fit for ships drawing from seventeen to eighteen feet, and if it were in the enemy's possession, it would afford him every facility for blockading the bay, or penetrating into the western channel. The fort will protect this anchorage, partly by its own fire, and partly by the fire of batteries erected in time of war under its protection. 2d. Occupying the eastern point of Dauphin Island, this fort forms a kind of tete du pont, by which troops may at all times be thrown into the island, to prevent an enemy from establishing himself in it, and cutting off the communications, mentioned above, between Lake Pontchartrain and Mobile bay. 3d. This fort, to the east point of Dauphin Island, will serve as a depot of all the means and stores of armament, ammunitions, and provisions, necessary to act with the navy; and defend, by temporary batteries, the several passes between the islands above mentioned, which cover the interior channel of navigation, uniting New Orleans, by Lake Pontchartrain, with Mobile bay.

As to the dimensions of the fort to be established on the eastern point of Dauphin Island, if we consider that it will have a passage to defend of the same breadth as the passage defended by the fort on Mobile Point; that it must, moreover, bear fires upon the anchorage south of the island; that it lies more distant from succors than Mobile Point; and that, in time of war, it must serve as a depot for the stores and armament necessary for the protection of the coasting trade and navigation to the west of the bay, we must conclude that its strength and dimensions can not be made inferior to those of the fort projected at Mobile Point.

I have the honor to remain, colonel, very respectfully, your most obedient humble servant,
BERNARD, Brig. Gen.
To Colonel W. K; Armistead, Chief Engineer. Engineer Department.https://en.wikipedia.org/wiki/Walker_Keith_Armistead

 A true copy. J. L. SMITH, Lieutenant Engineers.


                                                                                                            Washington, April 10, 1820.
Colonel:
I have the honor of transmitting to you the motives for which, in my opinion, the fort projected by the board to occupy Mobile Point cannot be reduced in its dimensions, without interfering with its objects.

You will find, in the report presented by the board, (1818,) that fifty-four pieces of the armament of the fort were destined to batter on the sea side, and an equal number on the land side. But fifty-four pieces are not too many to defend a channel of nearly one mile in breadth, and of depth sufficient to admit vessels drawing fifteen feet; and that number of guns, as well as the dimensions of the fort, would have been augmented, if the board had not taken into consideration that it was purposed to strengthen the defense of the channel by gun-boats acting in co-operation with the forts.

By land, the fort is exposed to a regular attack on every side. It was, therefore, necessary to give it sufficient means of defense, to allow time for succors to arrive before it could be taken. If we consider that on this frontier the population is widely scattered, we must conclude that a longer time will be necessary to assemble the militia there than on other points, and that the fort must be constructed with sufficient strength to resist an invading enemy, until it can be relieved.

I shall only add one consideration to those which I have exposed before. If, in consequence of the acquisition of the Floridas, Pensacola become a naval depot and a harbor of rendezvous, Mobile Bay would be a most favorable place of arms for an enemy to operate from thence upon the naval establishments of Pensacola.

These motives, joined to those which I have had the honor of addressing to you on the 8th instant, have brought complete conviction (at least to my mind) that the forts projected by the board at Dauphin Island and Mobile Point cannot be diminished in their dimensions without exposing that important position to be insufficiently defended.

I have the honor,
Sec. BERNARD, Brig. Gen.

To Colonel W. K. Armistead, Chief Engineer.
A true copy: J. L. SMITH, Lieutenant Corps of Engineers.