Missouri was kept in the Union by its means, Tennessee and Kentucky were restored, the National armies were enabled to push to the Gulf States and secure possession of all the great rivers and routes of internal communication through the heart of the Confederate territory.

On the 10th of April, 1862, the President issued the following proclamation:

It has pleased Almighty God to vouchsafe signal victories to the land and naval forces engaged in suppressing an internal rebellion; and at the same time to avert from our country the damages of foreign intervention and invasion.

During all this time the author of this plan remained unknown, except to the President and his Cabinet, who feared to reveal the fact that the Government was proceeding under the advice and plan of a civilian, and that civilian a woman. Shortly after the capture of Forts Henry and Donelson a debate as to the author of this campaign took place in the House of Representatives.[2] The Senate discussed its origin March 13. It was variously ascribed to the President, to the Secretary of War, and to different naval and land commanders, Halleck, Grant, Foote, Smith, and Fremont. The historians of the war have also given adverse opinions as to its authorship. Draper's "History of the Civil War" ascribes it to Gen. Halleck; Boynton's "History of the Navy" to Commodore Foote; Lossing's "Civil War" to the combined wisdom of Grant, Halleck, and Foote; Badeau's "History of the Civil War" credits it to Gen. C. F. Smith; and Abbott's "Civil War," to Gen. Fremont.

But abundant testimony exists proving Miss Carroll's authorship of the plan, in letters from Hon. B. F. Wade,[3] Chairman of the Committee on the Conduct of the War; from Hon. Thos. A. Scott, Assistant Secretary of War; from Hon. L. D. Evans, former Chief-Justice of the Supreme Court of Texas (entrusted by the Government with an important secret mission during the war); from Hon. Orestes A. Bronson, and many other well-known public men; from conversations of President Lincoln and Secretary Stanton; and from reports of the Military Committee of the XLI., XLII., and XLVI. Congresses.[4] So anxious was the Government to keep the origin of the Tennessee campaign a secret, that Col. Scott, in conversation with Judge Evans, a personal friend of Miss Carroll, pressed upon him the absolute necessity of Miss Carroll's making no claim to the authorship while the struggle lasted. In the plenitude of her self-sacrificing patriotism she remained silent, and saw the honors rightfully belonging to her heaped upon others, although she knew the country was indebted to her for its salvation.

Previous to 1862 historians reckoned but fifteen decisive battles[5] in the world's history, battles in which, says Hallam, a contrary result would have essentially varied the drama of the world in all its subsequent scenes. Professor Cressy, of the chair of Ancient and Modern History, University of London, has made these battles the subject of two grand volumes. The battle of Fort Henry was the sixteenth, and in its effects may well be deemed the most important of all.[6] It opened the doors of liberty to the downtrodden and oppressed among all nations, setting a seal of permanence on the assertion that self-government is the natural right of every person.

But it was not alone through her plan of the Tennessee campaign that Miss Carroll exhibited her military genius; throughout the conflict she continued to send plans and suggestions to the War Department. The events of history prove the wisdom of those plans, and that had they been strictly followed, the war would have been brought to a speedy close,[7] and millions of men and money saved to the country.

Upon the fall of Fort Henry, February, 1862, she again addressed the War Department, advising an immediate advance upon Mobile or Vicksburg. In March, 1862, she presented a memorial and maps to Secretary Stanton in person, in regard to the reduction of Island 10, which had long been a vain effort by the Union forces, in which she said:

The failure to take Island 10, which thus far occasions much disappointment to the country, excites no surprise to me. When I looked at the gun-boats at St. Louis, and was informed as to their powers, and that the current of the Mississippi at full tide runs at the rate of five miles per hour, which is very near the speed of our gun-boats, I could not resist the conclusion that they were not well fitted to the taking of batteries on the Mississippi River, if assisted by gun-boats perhaps equal to our own. Hence it was that I wrote Col. Scott from there, that the Tennessee River was our strategic point, and the successes at Forts Henry and Donelson establish the justice of these observations. Had our victorious army, after the fall of Fort Henry, immediately pushed up the Tennessee River and taken position on the Memphis and Charleston Railroad, between Corinth, Miss., and Decatur, Ala., which might easily have been done at that time with a small force, every rebel soldier in Western Kentucky and Tennessee would have fled from every position south of that railroad. And had Buell pursued the enemy in his retreat from Nashville, without delay, into a commanding position in North Alabama, on the railroad between Chattanooga and Decatur, the rebel government at Richmond would necessarily have been obliged to retreat to the cotton States. I am fully satisfied that the true policy of General Halleck is to strengthen Grant's column by such a force as will enable him at once to seize the Memphis and Charleston Railroad, as it is the readiest means of reducing Island 10, and all the strongholds to Memphis.

In October, 1862, observing the preparations for a naval attack upon Vicksburg, Miss Carroll again addressed the Secretary of War in the following memorial:

As I understand an expedition is about to go down the river, for the purpose of reducing Vicksburg, I have prepared the enclosed map in order to demonstrate more clearly the obstacles to be encountered in the contemplated assault. In the first place, it is impossible to take Vicksburg in the front without too great a loss of life and material, for the reason that the river is only about half a mile wide, and our forces would be in point-blank range of their guns, not only from their water-batteries which line the shore, but from the batteries that crown the hills, while the enemy would be protected from the range of our fire.

By examining the map I enclose, you will at once perceive why a place of so little apparent strength has been enabled to resist the combined fleets of the Upper and Lower Mississippi. The most economical plan for the reduction of Vicksburg now, is to push a