A KEY TO UNCLE TOM'S CABIN. By Harriet Beecher Stowe. Boston: Published by Jewett & Co. For sale at the office of the National Era, by Lewis Clephane, and by the bookstores generally.

  The long-promised book is at last published. It embodies the original facts and documents upon which Uncle Tom's Cabin was founded, and forms a volume of 262 pages. We were among those who were inclined to doubt the expediency of such a work. The story spoke for itself, and its truthfulness was attested by the heart of Humanity. Admit the possession of absolute power, such as the Slave Code confers on the master, and just such consequences must follow as are portrayed in Mrs. Stowe's novel. No man who understands what human nature is, and knows how to reason, and is not warped by prejudice, will deny this. He who does deny it, will scarcely be convinced by any documentary evidence that can be produced. He will raise precisely the same objections to the facts that he raised against the representations of the story—namely, that they are so constructed and arrayed as to convey a false impression. For this reason, and because we apprehended that the collection of such facts and documents could be easily collected and submitted to the Public, might arouse the bitter antagonism of the South, and close its heart to the more winning appeals of Mrs. Stowe through her fictitious narrative, we could have wished that she had let her assailants contradict and silence themselves, and given us another work of the class to which Uncle Tom's Cabin belongs. And this we know would have been more in accordance with her taste. She says, with great truth we doubt not, that "this work is one which has been written with no pleasure, and with much pain. In fictitious writing, it is possible to find refuge from the horrid and the terrible, by inventing scenes and characters of a more pleasing nature. No such resource is open in a work of fact; and the subject of this work is one on which the truth, if told at all, must needs be very dreadful. There is no bright side to Slavery, as such. Those scenes which are made bright by the generosity and kindness of masters and mistresses would be brighter still if the element of Slavery were withdrawn. There is nothing picturesque or beautiful in the family attachment of old servants, which is not to be found in countries where these servants are legally free. * * * * Slavery, therefore, is not the element which forms the picturesque and beautiful of Southern life."

  Mrs. Stowe was aware that if she did not undertake a work of this sort, somebody else would; and she preferred to do it herself, rather than have it done in an intolerant and a severe spirit. She has discharged what she considered her duty, with fidelity, ability, and kindness. She demonstrates her accurate knowledge of the law of Slavery, and her familiarity with its practical workings. There is not a character in Uncle Tom's Cabin for which she does not find a counterpart, not an incident for which she does not present a parallel. It is sheer nonsense to question the facts and documents she submits; for the accompanying evidence is such, that if slaveholders assail it, they but repudiate their own testimony. Throughout the work, she takes every legitimate occasion to relieve the dark picture, by bringing out what is excellent in Southern character and institutions. Her war is not on the Southern People, but on a system which is intrinsically barbarous and exceptional among the institutions of our country. She assumes for human nature in the North no superior virtue. She does not sit in judgment upon character, but upon institutions; and by an array of facts not to be questioned, furnished by slaveholders themselves, she demonstrates that all that is peculiar to Slavery, as distinguishing it from free labor, is "evil, and only evil, and that continually."

  And is this surprising? Have the American People yet to learn that Freedom is the right of man, and the necessary condition to Progress? That Slavery is a state of violence, degrading to human nature, and an obstacle to all progress? That Free Labor is a blessing, and Slave Labor a curse? Can any American, who has not forgotten that our Fathers rebelled against the British Government because it asserted the right—not to convert them into property, but—to appropriate to their own use a portion of their property, without their consent, and justified their rebellion by affirming the equal rights of all men to life, liberty, property, and happiness, deny that the Law which subjects one man to the will, and for the paramount benefit of, another, making not only his earnings but himself, body and soul, the property of that other, is and must be, "evil, only evil, and that continually." And yet, for proclaiming and proving this truth, Mrs. Stowe will fall under the bitterest maledictions of a portion of her countrymen. She will be charged with fanaticism, with bigotry, with want of patriotism, with treason against the Union; fanaticism, because she believes Despotism a sin against God and man; bigotry, because she believes Slave Labor is evil, and Free Labor good; hatred of her country, because she seeks her country's advancement by the removal of her country's curse; treason against the Union, because she has devoted her noblest energies to the overthrow of the one great Evil that disturbs its harmony and jeopards its existence.

  But she can afford to be abused. The very ferocity of her enemies bears witness to her power; the world acknowledges her genius, and oppressed, down-trodden Humanity everywhere will rise up and call her blessed. She will live, her fame forever brightening, and her good deeds bearing fruit forever, while the miscreants who now ruthlessly assail her shall be reaping their reward, with the Neros and Haynaus of mankind, in the execrations of posterity.