Says Thomson: "In giving a description of this valuable herb, I shall be more particular, because it is the most important article made use of in this system of practice, without which it would be incomplete, and the medical virtues of which, and the administering it in curing disease, I claim it as my own discovery. The first knowledge I ever had of it was obtained by accident more than forty years ago (1780), and never had any information whatever concerning it, except what I have gained by my own experience. A great deal has been said of late about this plant, both in favor and against its utility as a medicine; but all that the faculty have said or published concerning it only shows their ignorance on the subject; for there is very little truth in what they have stated concerning its medical properties, except wherein they have admitted it to be a certain cure for the asthma, one of the most distressing complaints that human nature is subject to. It is a truth which cannot be disputed by any one, that all they have known about this article, and the experiments that have been made to ascertain its value, originated in my making use of it in my practice."
In the course of my practice, a number of the doctors discovered that the medicine I make use of produced effects which astonished them, and which they could not account for; this induced them to conclude that because it was so powerful in removing disease it must be poison. This, I think, can be very satisfactorily accounted for; they have no knowledge of anything in all their medical science (?) which is capable of producing a powerful effect upon the human system, except what is poisonous, and therefore naturally form their opinions agreeably to this erroneous theory. There is a power to produce life, and a power to produce death, which are of course directly opposed to each other; and whatever tends to promote life cannot cause death, let its power be ever so great. In this consists all the difference between my system of practice and that of the learned doctors. In consequence of their thus forming an erroneous opinion of this herb, which they had no knowledge of, they undertook to represent it as a deadly poison; and in order to destroy my practice, they raised a hue and cry about my killing my patients by administering it to them. Some of the faculty even made oath that it was poison, and when taken into the stomach, if it did not cause immediate vomiting, it was certain death. It is unnecessary for me now to point out the falsity of this, for the fact is pretty well known that there is no death in it; but, on the contrary, there is no vegetable that the earth produces more harmless in its effects on the human system, and more powerful in removing disease and promoting health.
There is no mention made of this herb by any author, that I have been able to find, previous to my discovering it, excepting by Linnaeus, who has given a correct description of it under the name of Lobelia Inflata; but there is nothing said of its medical properties; it is therefore reasonable to conclude that they were not known till I discovered it, and proved it to be useful. When the faculty first made the discovery that I used the Emetic Herb in my practice, they declared it to be a deadly poison; and while persecuting me by every means in their power, and representing to the world that I killed my patients with it, they were very ready to call it my medicine, and allow it to be my own discovery; but since their ignorance of it has been exposed, and they find it is going to become an article of great value, an attempt seems to be made to rob me of all the credit for causing its value to be known, and the profits which belong to me for the discovery. In which some who have been instructed by me are ready to join, for the purpose of promoting their own interest at my expense.
Dr. Thatcher, in his Dispensatory, has undertaken to give an account of this herb; but is very erroneous, except in the description of it, which is nearly correct. It appears that all the knowledge he has on the subject as to its virtues, is borrowed from others, and is probably derived from the ridiculous ideas entertained of its power by those doctors who knew nothing about it, except what they gained by my making use of it, as has been before stated. As to its being dangerous to administer it, and that if it does not puke it frequently destroys the patient, and sometimes in five or six hours; and that even horses and cattle have been supposed to be killed by eating it acci-dently, is as absurd as it is untrue, and only proves their ignorance of the article. He tells a melancholy story about the Lobelia Inflata being administered by the adventurous hand of a noted empiric, who, he says, frequently administered it in a dose of a tea-spoonful of the powdered leaves, and often repeated; which, he says, furnishes alarming examples of its deleterious properties and fatal effects. This, there is no doubt, alludes to me, and took its rise from the false statements circulated about me at the time of my persecution, to prejudice the public against my practice. It is true the dose that I usually prescribe is a teaspoonful of the powder; but that it ever produced any fatal effects is altogether incorrect, and is well known to be so by all who have any correct knowledge on the subject.
What is quoted in the Dispensatory, from the Rev. Dr. M. Cutler, concerning this herb, is, in general, correct, particularly as it regards its being a specific for the asthma; though he labored under many mistaken notions about its effects when taken into the stomach. He says: "If the quantity be a little increased, it operates as an emetic, and then as a cathartic, its effects being much the same as those of the common emetic and cathartics." In this he is mistaken, for it is entirely different from any other emetic known; and as to its operating as a cathartic, I never knew it to have such an effect in all my practice. And I certainly ought to know something about it, after having made use of it for about twenty years, and administering it in every form and manner that it can be given, and for every disease that has come within my knowledge. It appears that all the knowledge he and other doctors have got of this herb being useful in curing disease, particularly in the asthma, was obtained from me; for when I was persecuted, I was obliged to expose my discoveries to show the falsity of the indictment. Dr. Cutter was brought forward as a witness at my trial, to prove the virtues of this plant by his evidence that he cured himself of the asthma with it. He says the first information he had of its being good for that complaint was from Dr. Drury, of Marblehead. In the fall of the year 1807, I introduced the use of the Emetic Herb, tinctured in spirit, for the asthma and other complaints of the lungs, and cured several of the consumption. In 1808, I cured a woman in Newington of the asthma, who had not laid in her bed for six months. I gathered some of the young plants not bigger than a dollar, bruised them, and tinctured them in spirits, gave her the tincture, and she lay in bed the first night. I showed her what it was, and how to prepare and use it, and by taking this and other things according to my direction, she has enjoyed a comfortable state of health for twelve years, and has never been obliged to sit up one night since. The same fall I used it in Beverly and Salem, Mass., and there can be no doubt but all the information concerning the value of this article was obtained from my practice.