mind. The most apparent of these was the vapor expired breathing. I recollected how, in former times, the stage horses, driven rapidly into my native village of a winter morning, had clouds of vapor wreathing upward from their nostrils, while the icicles of condensation were hanging below. The nurse, who stands over the dying, holds a mirror before the mouth and nose, and considers that life is only extinct when vapor ceases to be formed. Then came to mind the solution of that great mystery of physiology, why the arteries are empty at death, which so long hindered the discovery finally made by Harvey.

In the state in which chemistry was, even as late as the time of John Bell, the chemical power of the heat produced by respiration at the lungs could not have been understood.

SECTION II.

Publication of the Theory, in 1846, in “A treatise on the Motive Powers which produce the Circulation of the Blood.” Its Reception: Critique in the New York “Journal of Medicine,” September, 1846. My Reply, in the same Journal, March, 1847.

To Dr. Marcy.—In the years immediately succeeding 1840, (in which year, as you will recollect, I had the honor to receive your countenance and advice respecting my theory,) I was almost exclusively devoted to the revision and enlargement of my historical works; but early is 1846, having determined on making the tour of the United States, I resolved first to prepare my theory for the press. In the introduction, I remarked, “The house of clay in which the mind dwells must receive a portion of its care; and that which I have bestowed on mine has proceeded on a belief in the truth of the theory herein advocated, as undoubting as that in the laws of gravitation; and when any new fact, or any remark of an author, relating to my theory came under my observation, I noted it down and laid it by with its kindred. About to set out on a long journey, and aware that my field of vision had thus enlarged, I felt it my duty to put together the principal of my remarks, that I might so leave the subject, that, in case anything should prevent my return, it would be in a form equal to the present slate in which the theory exists in my own mind.”

The time I had spent in devotion to this theory, the many rebuffs I had met in seeking to promulgate it—sometimes, unhappily, affecting my social life—had made painful the duty of publishing it. My historical works had been received with favor; but I believed that, in publishing this, it would be charged against me that I chose a subject unsuited to my sex. I therefore said, in my preface, “This is not so much a subject which I chose, as one which chooses me; and if the Father of Lights has been pleased to reveal to me from the book of his physical truth a sentence before unread, is it for me to suppose that it is for my individual benefit? or is it for you, my reader, to turn away your ear from hearing this truth, and charge its great Author with having ill-chosen his instrument to communicate it?”

As I passed southward on my journey, I left, March, 1846, my manuscript in the hands of Wiley & Putnam, in N. York:[4] to be published at my expense. During the six months in which I was absent on my travels, my book was published; and the publishers sent copies, as directed by me, to many of my personal friends, and to several physicians. They sent other copies, which procured notices, some of which were favorable, particularly one from the London Critic, and others, the reverse. As few copies of the book sold, I was not remunerated for the cost of publication. The copies sent to physicians were mostly unacknowledged—received in cold, if not contemptuous, silence. But my family physician, the worthy and learned Dr. Robbins, to whom I dedicated the work, ever upheld me. He answered my questions, gave me instructions, and showed me post-mortem dissections; and to those who asked him if he believed in my theory, he wisely replied, “Mrs. Willard is right as far as she goes.” He knew that I made no pretensions to understand the vast variety of medical subjects not connected with the circulation, and that I never doubted his skill or disputed his prescriptions. An honest man, and a skilful physician, he deserved and had my unfailing confidence. And if, by reason of what I knew, I had prolonged my life, he had the longer kept a good and faithful patient. Lady-friends, to whom I had sent my work, had sometimes referred it to their medical advisers; and thus Dr. Hiester, an eminent physician of Reading, Pa., became a believer. And in the same way, the eminent Dr. Cartwright, then of Natchez, and President of the State Medical Association of Mississippi, came to a knowledge of those principles, which, as we shall hereafter show, he so remarkably elucidated.

In September, 1846, the New York Journal of Medicine, then edited by Dr. Charles A. Lee, contained a review or critique on my work, which, if the history of the theory shall hereafter become a matter of special interest, may, with my reply, contained in the March number of 1847, furnish any examiner with the full state of the question at that period.

The learned reviewer showed himself acquainted with the subject as it then stood, and with its history in the past. He held that the heart’s action, “the contractile power of the cardiac walls,” is the main spring or primum mobile, from which the circulating force proceeds, notwithstanding the great discrepancies as to what that force is; and while he objected to my theory, that it did not show any distinct measure of force, he said that, while Borelli estimated the contractive power of the heart at 180,000 pounds, Keill stated it at five ounces, Sir Charles Bell at 51 pounds, Carpenter at 51½, and Hales at 50. He abandoned, however, Harvey’s idea that the heart was the only organ of circulation. He believed that it was assisted by the contractile power of the arteries, by the movement of the ribs and chest in respiration, by capillary attraction, muscular contraction in exercise, and several other forces; one of which, the attraction of the venous blood for the pulmonary cells, had been recently pointed out by Dr. Draper. The author did not suppose he was bringing forward any new truths; “but,” said he, as an introduction to his account of my theory, “are we not sometimes in danger of forsaking old truths for new theories?”

Of my theory, he says: “The mere statement of it must satisfy our readers that it is wholly untenable. It is well known that heat is generated in every part of the system as well as the lungs. Whenever oxygen and carbon unite, there it is developed; but it is imparted to the solids equally with the fluids; it maintains the temperature of the whole body by radiations from the points where it is generated.” ... “It is believed that all those functions of the organism which are necessary for the preservation of life, contribute directly or indirectly to the production of animal heat; so that it is developed at every point at which metamorphosis is occurring, and therefore not merely in the lungs, but in the whole peripheral system.”

The writer then observes, that “the heat of the venous blood as it reaches the right side of the heart (according to Davy), varies only two or three degrees from that of the aorta. Granting, then, that the blood receives three degrees in the lungs, it is very evident that the expansion produced by it would be too small to be appreciable. The cause, then, is insufficient to produce the effects.” The writer gives me credit for having ingeniously