129 [Dr. Charles T. Jackson's Statement of the History of his discovery of the means of preventing all sensations of pain in Surgical operations, by administration of Vapor of pure Sulphuric Ether mixed ivith'air> by pulmonary inhalation.] Boston, December 18, 1851. Hon. Wm. H. Bissell, Chairman of a Select Committee on the Ether discovery, fyc,— Sir : I have the honor of laying before you a brief account of tire ori- gin of the discovery of the anaesthetic effects of pure sulphuric ether vapor mixed with air. This paper is ihe original rough copy of the memorial I have sent to his Excellency Baron Alex. Von Humboldt, of Berlin, to lay before the Royal Academy of Berlin, and was prepared by request of the Hon. Secretary of State of the United States "for Baron Hum- boldt's use," and was transmitted by me to the Department of State. I trust you will find in it and in the evidence I shall have the honor to send to you, to lay before your committee, ample proofs, that the dis- covery of etherization arose with me, and was introduced into surgical practice under my directions. Any points not perfectly clear to you, I shall be happy to write to you about, and give you any and all the information I possess concerning this discovery. I regret that the very short notice you gave me of your having the subject of this discovery before your committee, will not allow me lo make a transcript of the original paper, and therefore I beg you will allow me to present it in my own hand-writing, which is not quite so , good as that of an expert penman, but I trust will be found clear and 1 legible enough for the printers to set up, in case the documents are printed for information of Congress. While I was a student in medicine, in 1825, '26, '27 and '28, 1 was engaged in chemical and physiological researches connected with my professional studies, and had read with deep interest the curious re- searches of the late Sir H. Davy, on the physiological effects of va- rious gases, when inhaled into the lungs, and I repeated all those that were not considered imminently dangerous, for the purpose of realizing ¥ their effects on the system. Among the other gases I inhaled very frequently, and administered to others, the protoxide of nitrogen, (exhilarating gas,) and was thus made perfectly familiar with its physiological effects. Subsequently I thought much of Davy's suggestion, that protoxide of nitrogen might possibly be employed in mitigating the pain of ^urgjcal operaiion,and on my return from Europe, where I had beejMOti$gfj^yefriyself in the sciences of medicine and surgery, I determinedrtd trjr the epects of lhat gas in every possible way, and I did, in 1837;4hii^lhal>i#ad produced the state of insensibility required, by adminisYenjfg' to several young men the protoxide of nitrogen, through a very small aperture, closing the nostrils at the lime, so as to exclude air from the lungs, but I found that I only had produced a partial and a dangerous state of asphyxia, and that the patients had not lost sensation, as was proved by pulling their hair, and by touching them. I came lo the conclusion, therefore, that anaesthesia, or insensibility to pain, can not be produced by the in- halation of that gas, as proposeoS by Sir H. Davy, and therefore aban- doned that method. 10 I 130 had frequent occasion to experiment with chlorine gas, and hnti act - dents myself, as with mv pupils, by the breakage o( vessels hied win this gas, and had inhaled it into the lungs. Vapor of alcohol \\n>m that time the remedy we used for relief, and not finding it to answer me pupefse satisfactorily, I soon after tried the inhalation oi sulphuric ether rapor, which from 1837 to 1851. was the means in habitual use m my laboratory for relieving persons from the effects of the action of chlorine in the lungs. It will be seen by the deposition of Dr. Wm. 1«. Cnan- ning, that I administered it to him in 1846, in the month of March. [Vide Dr. Martin Gay's statement—testimony, p. 5.] This was alter I had discovered its power of paralyzing the nerves of sensation, as also appears in his deposition, and in those of John H. Blake, Esq., and Dr. George T. Dexter and D. J. Brown's letters, the deposition of Henry V. Fowie and Dr. S. A. Bemis. In the winter of 1841-2, I made the dis- covery of anresihesia by ether vapor, as is proved by the depositions above referred to. < • -a The history of this discovery is deemed interesting to the scientific world, and 1 shall therefore give the facts and my induction in detail. The origin of the discovery, you will perceive, was from an accident, but the induction, by which the discovery itself was made, was truly sci- entific and legitimate in all respects. The circumstances were as fol- lows:—In the winter of 1841-2, I was employed to give a few lectures before the Mechanics Charitable Association, in Boston,'and in my last lecture, which 1 think was in the month of Febuary, I had occasion to show a number of experiment in illustrations of the theory of volcanic eruptions, and from my experiments I prepared a large quantity of chlorine gas, collecting it in gallon glass jars over boiling water. Just as one of these large jars was filled with the pure chlorine, it overturned and broke, and in my endeavors to save the vessel 1 accidentally got my lungs full of chlorine gas which nearly suffocated me, so that my life was in imminent danger. I immediately had ether and ammonia brought to me, and alternately inhaled them with great relief. The next morning my throat was severely inflamed, and very painful, and I perceived a distinct flavor of chlorine in my breath, and my lungs were still much oppressed. I determined, therefore, to make a thorough trial of the ether vajpor, and for that purpose went into my laboratory, which adjoins my house ia Somerset street, and made the experiment from which the discovery iM anaesthesia was induced. I had a large, snorijvof perfectly pure washed sulphuric ether, which was prepared in the Taooratory of my friend, Mr. John H. Blake, of Boston. I took a bottle of that ether, and a folded towel, and seating myself in a rocking chair, and placing my feet in another chair, so as to secure a fixed position, as I reclined backward in the one in which I was seated. Soaking the towel in the ether, I placed it over my nose and mouth, so as to inhale the ether mixed with, the air, and began to in- hale the vapor deeply into my lungs. At first the ether made me cough, but soon that irritability ceased, and I noticed a sense of coolness, fol- lowed by warmth, fulness of the head and chest, with giddiness and ex- 131 hilaration. Numbness of the feet and legs followed, a swimming or floating sensation, as if afloat in the air. This was accompanied with entire loss of feeling, even of contact with ihe chair in which I was seated. I noticed that all pain had ceased in my throat, and the sensa- tions which I had were of the most agreeable kind. Much pleased and excited, 1 continued the inhalation of the ether vapor, and soon fell into a dreamy state, and then became unconscious of all surrounding things. I know uot how long I remained in that state, but suppose that it could not be less than a quarter pf an hour, judging from the degree of dryness of Hie cloth, which during this state of unconsciousness, had fallen from my mouth and nose and lay upon my breast. As I became conscious I observed still there was no feeling of pain in my throat, and my limbs were still deeply benumbed, as if thejierves of sensation were fully paralyzed. A strange thrilling now began to be felt along the spine, but it was not in any way disagreeable. Little by little, sensa- tion begaa to manifest itself; first, in the throat and body, and gradual- ly extended to the extremities, but it was some lime before full sensa* tion returned, and my throat became really painful. Reflecting upon these phenomena, the idea flashed into my mind, that I had made the discovery I had for so long a time been in quest of—a means of rendering the nerves pf sensation temporarily insensible to pain, so as to admit of the performance of a surgical operation on an individual without his suffering pain therefrom. That I did draw this inference, and did fully declare my. unqualified belief in both the safely and efficiency dent, and I allowed him to call himself my pupil, and I advised him to aitend the lectures at the Medical College, of this city, and endeavored to instruct him in the first principles of human anatomy. I soon found that be was too ignorant to be capable of learning the medical profession, though I thought in tbe.course of time he might learn enough to be- come a surgeon dentist. He was a well dressed and plausible man, and although 1 knew him to be anignoramus in all matters of science, I thought he could perform the very simple operations that 1 was about to commit to him, namely, ihe administration of ether lo gome of ihe patients whose teeth he was about to extract. His office, I knew, was' frequented by the lower and credulous class of people, such as were atlracled by his quack advertisements, with which he filled our daily newspapers. 1 had for years ceased to practice medicine and surgery, and had no opportunity of operating in any case ; my business having for some years become that of a chemist and geologist. I therefore, on the 30th day of September, 1816, induced this dentist, Morton, \o'lest my discovery on a person whose teeth he was about lo extract, commit- ting it to him in the presence of two of my pupils, Mr. George Orville Barnes, and Mr. James Mclntyre, whose sworn depositions are for- warded to you with the other testimony. Mr. Morton, at the time I communicated to him my discovery, was wholly ignorant of the nature of ether, as is fully proved by the testimony above mentioned. He did not come to my pffice to ask any questions about ether, and did not mention it until after I had communicated lo him my discovery He came only for the purpose of borrowing an India-rubber cloth gas-bat? which he intended to fill with air and pretend it was protoxide of ni- 135 trogen, which Mr. Hoface Wells had been exhibiting in this city, in 1844, but without any success in his attempts to prevent pain in extract- ing teeth. Mr. Morion wished to impose upon one of his patients, or to operate upon the imagination. He was going out of my office with the bag, when it suddenly occurred to me that 1 could induce him to test my method by etherization. I therefore, just as he was going out of the office, went to him and took the gas-bag out of his hands, and lead- ing him into my laboratory, in presence of Mr. George O. Barnes, and Mr. James Mcltityre, I told him of my discovery of a means of pre- venting all sensations of pain in surgical operations, by the administra- tion of the vappr of pure sulphuric ether, (oxide of ethyle,) mixed with air. He was evidently astonished at what I told him, and was so much surprised that he ran first to one of my students and then lo the other, asking them if the ether « Would work '' as I said it would. He asked if it was "a gas!!! " If I " had any of it," &c. 1 told him it was a liquid, and took down from my shelf in ihe laboratory, ihe bottle half full of ether, and let him smell of it. He then asked me how I used it, and I showed him how to administer it, on a handkerchief. Morton's words were, when I told him the patient could be rendered perfectly un- conscious and free from all sensation of pain, by ether,—" Will it do it ? Are you sure ? " and he appeared to be greatly delighted and danced about the laboratory-room, when I replied, " Yes, I know it." He then asked me to let him lake the bottle of ether which 1 had just shown him ; but since it had been standing in the laboratory for some years, I feared it might have become deteriorated ; I therefore advised him to go to Mr. Burnett, one of our best apothecaries, and get some recently prepared pure sulphuric ether. Mr. Morton asked me if there was danger in breathing the ether. I said, No ; there is no danger if you follow my directions. I then repeated my directions, with all the requisite precau- tions—told'him exactly the effects of the ether upon the patient, and en- deavored to persuade him to iryit on his oWn person. He promised to fry it, but there is no reason to believe that he ever did, himself, inhale it, go as to produce insensibility to pain, or unconsciousnes. He did, however, administer it to Eben Frost, a laborer, and extracted a tooth from his jaw\ and ihe next morning he Came to my laboratory and re- ported the result. Said that it worked exactly as I said it would. " The patient Went right to sleep," aiid he " pulled his looth without his know- ing anything about it." 1 expressed no surprise, but regarded the re- sult as a matter of course, to be expected from the full etherization of the patient. I then proposed to have it further tested at ihe Massachusetls General Hospital, by a more severe operation, before publishing my results ; but Mr. Morton wished that I should conceal the discovery and let him have ihe use of it. This I declined doing, saying lhat 1 should communicate it to my medical friends, and when ready should publish it. At my urgent request, a few days after, Morton went to Dr. Warren and asked him to let him administer the " gas " to one of his surgical patients, and it was allowed ; but the experiment was not satisfactory. It was tried again with better results in another case—a fatty tumor of the shoulder being extirpated. I then saw Dr. Warren at his own house, told him that Mr. Morton was'operating under my directions, and 1 then engaged 136 Dr. Warren to allow the ether to be administered to a person who was about to undergo a capital operation, (amputation.) Dr. Warren con- sented to have the trial made, but said, "I wish you would come and ad- minister the ether yourself; I do not like to have such a quackish jellow as Morton about the hospital." Learning that the operation was to be performed at the end ol the week, and having engagements at a mine in Liberty, Md., 1 told Dr. Warren that I should be absent, and asked him to allow Morton, whom I had fully instructed, to administer the ether in the proposed case. The next morning, I receive'd a note from Dr. Warren, asking about jhe na- ture of the agent used, and requesting me to procure apparatus for its ad- ministration, for the hospital. I was, however, obliged by an appoint- ment I could not break, to go to Baltimore that very day, and was absent from Boston at the time of the operation, which was performed by Dr. George Havward, on the thigh. Soon as I returned, I accompanied Dr. Warren, and his son John M. Warren, to the Bromfield House, where the ether was successfully administered, and a large tumor was excised from the thigh of a man, who was rendered profoundly uncon- scious by means of ether vapor inhaled from a glass globe, into which it was admitted by the tubulaire. It is obvious enough to those who know the circumstances, why I engaged an ignorant man to introduce my discovery. I had already, before Mr. Morton came to Boston and set up as a dentist, endeavored to engage more responsible persons to make the trial of the ether in their practice ; but they declined doing so, knowing thai the medical and toxi- cologieal books declared it to be a dangerous experiment, while J insisted that it was not dangerous. They thought that in their medical capacity they would incur responsibility for any accidents that might happen, to their patient, and hence feared to act. I knew that Mr. Morton placed such implicit reliance upon my scientific and medical skill, as to be willing to perform, upon my medical responsibility, any experiment, the safety of which I guaranteed; and he was, therefore, easily persuaded by me to make ihe trial which I requested, I taking the whole respon- sibility, before two witnesses, Messrs. Barnes and Mclnlyre. Again, I knew that he could only be held responsible for the faithful perform- ance of the experiments repeated in the presence of the above-named witnesses. I did not even suspect the possibility of his setting up claims to the discovery, himself, for the idea was too preposterous to have entered ihe mind of any honest man of science. I was not then aware of his previous career of infamy, and knew him only as an ignorant but enterprising dentist, who had an extensive practice among the lower classes of society, and a reputation among them for extracting teeth. When I learned that he had betrayed my trust, and was offering for sale, for large sum> of money, the "secret " of my discovery, I called upon him and severely reprimanded him. He then denied that he had ever done any such thing, or had ever thought of claiming the discov- ery, and said he had never consulted any solicitor about taking out letters patent for it. He most emphatically denied ever having au- thorised any one lo publish an account of the experiment I had com- mitted to him, and concluded by offering me five hundred dollars to give him a quit claim to use the ether in dental surgery. This is ad- 137 % mitted in the pamphlets published by Morton, entitled the " Letheon, or who was the Discoverer?" He followed me to ihe door of his of- fice, and said, " It is understood, then, that you are to charge me five hundred dollars for it." My anger was in a measure appeased by his declarations that he never thought of claiming the discovery, and that he " had always said that he got it of Dr. Jackson." So I consented that he should continue to use" the ether in his operations, and went home and charged to Mr. W. T. G. Morton, five hundred dollars, in my account books. This money was never paid to me, nor shall I ever demand it of him. It proved that he had lied to me; that he had not only consulted a patent solicitor, but had actually formed a co-partner- ship with him ; and that patent solicitor was to manage matters for Mr. Morton, and receive one-third of the proceeds of the sales of patent rights in the United Stales, and one-half of that received for patents in Europe. It also is proved, that he did employ a clerk to publish in one of the newspapers of this city, the notice which he had so solemnly denied having authorized to be published. It was such a paper as would have been authorized only by a charlatan, and was strongly de- nouncd by me as such. Finding that I was in great danger of losing the credit of my discov- ery, I was foolish enough to listen to the advice of ihe patent solicitor, Eddy, whom I did not at the lime suspect of being interested with Mor- ton in his attempts to rob me of my discovery, and by his pretended friendly advice I allowed my name, under the following protest, to be used in procuring letters patent. This document, I found, was not the one that Mr. Eddy actually sent to the Patent Office, and that discovery led to an investigation, proving that Mr. Eddy was a co-partner with Mr. Morton. • • The protest dictated by me, and written in my presence, by Mr. Ed- dy, was as follows :-— li Dr. Jackson is extremely unwilling to take out a patent for anything applicable to the relief of .human suffering; but in order to secure the honor of this discovery, and to conform to the laws of his country in tratismittihg his rights to another, hereby consents," Sfc. Under his usual power of attorney, Mr. Eddy altered this as follows, and without my knowing it at the time of signing it. " Dr. Jackson, Willing to benefit Mr. W. T. G. Morton, assigns to him his rights to the interest, and requests the Commissioner of Palents to issue the patent in the name of W. T. G. Morton,"—or words to the same effect. Trusting that my injunctions had been faithfully carried out in the pa- pers, I signed them without reading them, and that was the origin of the whole mystery of my name having been associated with that of Mr. Morton in this patent so improperly obtained. Consulting the Commissioner of Patents, Hon. Edmund Burke, I learned that the patent was only good so far as my name was connect- ed with it, and by his advice I at once appealed to the public—de- stroyed the bond given me by Mr. Morton, and made the use of ether, in surgical operatipns, free to all mankind—and free it has been from that day, in spite of all attempts to speculate in human sufferings, for money, as was steadily persevered in by Mr. Morton and his asso- ciates. I went before the Massachusetts Medical Society, and volun- tarily offered my discovery freely to all medical men. U 13* I communicated it freely to the world, and laid the evidence that ll was my own discovery before the Acaderaie des Sciences, of France, by which learned body the award of the discovery was made to me, and the Monthyon prize voted therefor, as appears in the accompanying copy of the letter of M. Flourens, Perpetual Secretary of the Aeademie des Sciences. _.^^*.t »« ™ CHARLES T. JACKSON, M. D. Boston, Mass., Nov. 22d, 1851. Chloric Ether and Pure Chtoroform. In the winter of 1833, I prepared a very strong solution of cMeroform. in alcohol, following the directions published in the American Journal of Science and the Arts, for 1832, vol. xxii. p. 106, by Samueli Guthrie, Chemist, at Sackett's Harbor, and by A. A. Hayes, Esq., Chemist ©4 the Roxbury Chemical Works. [Am. Jonr. Science* for 1832, p. 163.) This kind o( cboric ether was used by me, and by other physicians at the time, in cases of asthma ; and. it was found t© be very servicable in those cases called spasmodic asthma. In 1834, while engaged in the practice of medicine, employing only my leisure hours in chemical pursuits, I had occasion to try the effect* of some of my strong chloric ether in relieving the pain of a carious tooih of a young woman, who was very unwilling to have the tooth ex- tracted. The immediate relief wbicb this remedy gave, and the per- manent cure of the toothache in tlhis case,.demonstrated! a new power in this valuable preparation; and there was an immediate call made upon me to furnisb other persons with this preparation. I then tried it on my own teeth, and took a phial of it to Dr. N. C. Keep, and Request- ed him to use it im deadening the pain in an inflamed eavious tooth, which he was about to fill or plug for me. He did .so,, and was greatly pleased wilb its effects, which were preferable to creosote*, then usually employed for the same purpose. 1 gave to keep, to Dr. Keep* the phial of strong ether, and he used it successfully in many subsequent operations, at hie office. I also prev pared phials of it for other dentists of Boston ; gave some of it to Dr. Josian Flagg, an eminent dentist of this city, who also used it with success.. I. then, bad so many, calls for it. that I could, not supply the demand, and in order to save myself further tsouble, employed Messrs. Furguson and Callender, Chemists of the Norfolk Laboratory,, in Rox- bury, to manufacture the strong caloric ether for sale,.and insinuated them how to prepare it of great strength' and parity. They made U for several years, and sold it nndet the name o£uChlarwl" tQidistinguish it from ordinary chloric ether of commerce, which is weaJb and ineffi- cient as an allayer of toothache. After I had made the discovery of the* anaesthetic properties of ether vapor, by inhalation of it mixed with air, I attempted to produce a similar effect by the strong- chloric ether, but the experiments did not prove satisfactory, prebobip on account of the large proportion of strong alcohol in it, and its being admin isteeed on a dry cloth. A wet sponge or cloth abstracts the alcohol from ehlorio ethet and leaves only pure chloroform, the water combining with; the alcohoL 139 1 did not think it so safe as pure sulphuric ether, and therefore pre- pared the latter. I included it, however, among the agents that would probably serve as a substitute for sulphuric ether, in my communica- tions subsequently made to Robert H. Eddy, Esq., the Patent Solicitor, and it was inserted in the patent taken out by him in the name of Mor- ton. In 1847, I learned from the French journals that M, Flourens had ■employed a mixture of chloroform and sulphuric ether as a substitute for pure sulphuric ether, as an anaesthetic agent; and soon after, that Mr. Waldie, a Scotch chemist, had suggested to Dr. Simpson, that^mre 'chloroform would serve as a substitute for the sulphuric ether, which he had been using, pursuant to my published directions. On the 1st of January, 1848, I published in the Boston Atlas, a very full account of the method of preparing pure chloroform, and gave full and minute instructions to an eminent druggist of this city, Mr. W. B. Little, how to prepare it on a large scale. T also publicly administered it to a number of persons, to Dr. John C. Warren, and to Mr. Joseph Wightman, at the u Warren dub," and to my pupils in my laboratory, and without any accident of any feind. I also prepared, and gave away, large qoahfities of pure chloroform, and of a mixture of chloroform and pure sulphuric ether, which I recom- mended as preferable to that more powerful and somewhat dangerous agent, chloroform. On the 1st of October* 1848, I published in a pamphlet edited by Mr. W. B. Little, a more full account of my experiments, and especial- ly of those made at the Mcljean Asylum for the Insane, by Dr. Luther V. Bell and myself, on previously insane patients, who were greatly relieved by this administration of the mixtore of ether and chloroform. No unpleasant accidents ever happened to any of the patients to whom I administered the preparation ; and I was generally successful, even in the most desperate cases of insanity/ in rendering the patient perfectly insensible and unconscious, which state gave rest to the agitated ner- vous system, and relieved the patient in a most remarkable manner. I urged the use of this agent in the treatment of intermittent fevers, in which it has since been successfully employed. Chloroform soon became cheap, and a common article in the drug- gists' shops, and was used with great carelessness, by uneducated drug- gists and other unscientific persons, and deaths soon began to alarm our community, from the want of skilful use of this powerful agent. I was called to administer remedies to persons thrown into dreadful convulsions, of many days continuance, from the improper administra- tions of pure, or rather- strong, chloroform, and so frequent was the abuse of this agent, that I was forced to denounce it as an unsafe sub- stitute for the ether originally proposed by me as a means for the super- induction of anaesthesia. I allowed its use when diluted with sulphuric ether, and instructed physicians in the mode of preparing the mixture in proper proportions. I have not known of any accident having taken place from the use oft the preparation presented by me, and I use it in my own family freely and without fear, in parturition, and in rendering my children insensible to paid while they have to undergo the operation of extraction of teeth. 140 Use of Anaesthetic Agents. Many substitutes have been proposed for sulphuric ether, in surgical operations. Among others, a Norwegian chemist proposed to employ the bi-sulphuret of carbon, which is made by passing vapor of sulphur over ignited charcoal. This preparation was immediately tried by me, first upon myself, with the most astonishing rapid production of entire unconsciousness. I then administered it lo Mr. George O. Barnes, and to Mr. George J. Dickenson, two of my pupils, who were rendered un- conscious in a few moments by this powerful agent; but I quickly dis- covered this experiment was eminently dangerous to life—partial as- phyxia taking place, so as to give me much anxiety as to the result. I therefore abandoned its. farther use* and denounced it as dangerous to life. A correspondent having urged me to make the trial of cenanthic ether made from oil of wine, 1 prepared a quantity of it, and made the ex* periment of full inhalations of it on my own person, with the most pain- ful results. The cenanthic ether producing severe headache, vertigot and nausea, which lasted for several days. I also read in the French newspapers, that aldehyde would serve as an anaesthetic agent, and I immediately prepared that article, and tried it on my oion person, with results like those produced by cenanthic ether. These two agents I therefore discarded, as unfit for inhalation. I made a long series of experiments on the compounds of metbyle, the radical of wood naptha, and found but one that would serve as an anaesthetic agent. It is that admixture of chlorine and methyle, analo- gous to the ter-chloride of formyle, or chloroform,'wbieh I found acted like chloroform, and like it was dangerous in its concentrated state, but not so when diluted with sulphuric ether. I therefore sometimes use it so prepared, and no accident has taken place from its use. Benzole was proposed by Mansfield, I think, as a substitute for chlo- roform. I have used it on my own person, and found it so irritating to the tonsils, as to forbid further trial. It seems lo act much like impure chloroform, but is not so active. Thus, it will be perceived that I have given every agent, known to myself, or prepared by others, a fair trial, experimenting first on myself in all cases, and then on such of my brave pupils as were willing to submit lo my experiments. .Thus far, no agent in safety can be compared tojny original pure washed sulphuric ether, inhaled freely, mixed with air; and I have never heard of a single fatal accident happening from the administration of this agent, as originally directed by me. It is unfortunate for mankind, that pare or concentrated chloroform was ever substituted for sulphuric ether, for all the prejudices against anaesthetic agents in the community arose from the fatal and disagree- able effects produced occasionally by that powerful agent. In the course of time the public will learn to discriminate between two very different substances, and will learn that the clear vapor of chloroform is likely to produce asphyxia, by drowning, if drawn into the lun^s with- out very large dilution with air. They will learn, also, that sulphurous acid often exists in laTge propor* tions in these anaesthetic agents; and that great care must be used in 141 the prepartion of them for inhalation, and that they should be thorough- ly examined by competent persons, before they are employed in the production of anaesthesia. Apparatus used for administering Anaesthetic Agents. I originally, in 1842, used a coarse towel, as the best for administra- tion of sulphuric ether by inhalation. I next used a large open-tex- tured serge, and afterwards, some more showy apparatus being called for, I directed the use of a large glass globular condensing receiver, with a tubulaire for the free admission of air, and a large orifice for applica- tion to the mouth. On the 2d or 3d of October, 1846, I loaned to Mr. W. T. G. Mor- ton, a large glass flask, with a large bent glass lube, reaching near to the bottom of the flask, and resting at its bent part loosely upon of the neck of the flask, so as to allow the air to be drawn down freely over the bottom and sides of the flask, and up the tube with the dis- solved ether vapor; this apparatus being much like that subsequently invented by Mons. Charrier, Surgical Instrument Maker, of Paris. This apparatus I did not like so well as a cloth or large sponge, and soon advised that its use be discontinued, and the sponge should be re- sumed. Soon, however, Dr. A. A. Gould proposed to affix Maures' syringe valves to the condenser globe, proposed by me, and I was sur- prised to learn that a patent had been secured for that alleged improve- ment, and that a large quanity of those " glass inhalers," as they were called, were offered for sale under the patent! ! The application of valves to the inhaler, was particularly unfortunate, and I advised at once to give up the use of such dangerous and suffocating instruments. One case of death from the use of chloroform in an inhaler of this kind, completed the overthrow of their use in physical practice, and they are now generally discarded among judicious surgeons and physicians, and the use of ihe sponge is resumed. The cause of asphyxia, so commonly produced in the early admin- istration of ether vapor at the Massachusetts General Hospital, I traced directly to the employment of those valved inhalers. In the weakened state of respiratory action under anaesthetic agents, the valves are not raised in attempts to breathe, and the patient is drowned by the pure ether or chloroform vapor. On the removal of the valve by my direc- tions, asphyxia at once ceased to occur at the hospital, and I had no oc- casion to employ the " oxygen gas to revive the patients," as I was re- quested to/do by one of the eminent surgeons of that institution, for no asphyxia happened after my advice was followed to throw aside the inhalers and use a sponge. The results of long experience have confirmed the facts that the use of pure washed sulphuric ether, (oxyde of ethyle,) as originally pre- scribed by me, and administered as I then directed, is the safest and best method of producing insensibility to the pain of surgical operations and unconsciousness, but that a mixture of one-fourth part of pure chlo- roform gives greater concentration to the power of the anaesthetic agent. I have the honor to be your most ob't, and respectful servant, CHARLES T. JACKSON, M. D., &c, &c.