NITROGENIUM OXYGENATUM.

Nitrous oxide (gas). NO.

Laughing gas.

The gas is slightly soluble in water.

Authorities. [Selected from numerous observations. -T. F. A.]

1 , Sir Humphry Davy, experiments on self, Researches Chem. and Philosophical, London, 1800; 2 , same, subsequent experiments with the gas mingled with the air; 3 , same, "when fatigued by a journey, I respired nine quarts of the gas;" 4 , same, "when fatigued by a journey, I respired seven quarts;" 5 , same, effects after having taken the gas, often as many as four times a day, for a fortnight; 6 , same, effects of inhaling the gas, in a tight box, into which twenty quarts of gas were thrown; 7 , same, effects on Mr. Toblin; 8 , same, on Mr. Clayfield; 9 , same, on Mr. Kinglake; 10 , same, effects on Mr. Burnet; 11 , same, on Mr. Edgeworth; 12 , same, on Mr. Southey; 13 , Pfaff, Nord. Archiv, 1804 (Frank's Mag., 3, 709), effects on Dr. Struve; 14 , same, on another individual; 15 , same, on another individual; 16 , Curtis, Bost. M. and S. Journ., 2, 425, effects in a lady, suffering from asthma; 17 , B. W. James, M.D., N. Am. J. of Hom., 1866, p. 517, effects in self; 18 , Jeannel, Gaz. Hebd., 1869, experiments on self; 19 , same, effects in another individual (taken for extraction of tooth); 20 , Braine, Brit. Med. Journ., 23 (1869), effects; 21 , Amory, N. Y. J. of Med., 1870, effects on self; 22 , Mitchell, experiments on friends, West Riding Lunatic Asylum Reports, 1871, p. 44, Mr. J.; 23 , same, Dr. N.; 24 , same, Mr. D.; 25 , same, Mr. H.; 26 , same, general effects; 27 , same, effects on self; 28 , Maclaren, Edin. Med. Journ., 1871, general effects; 29 , Mason, Lancet, 1873, p. 254, effects in a lady, who inhaled the gas to have a tooth extracted; 30 , Farrington, Am. J. Hom. M. M., 4, 105, effects of inhalation in a colored woman (with scrofulous glands); 31 , "S. W.," Lond. Med. J., 1873, "personal experience;" 32 , Br. Med. Journ., 1873, "personal experience of a medical man;" 33 , Thomson, Phil. Med. Times, 1873 (November 15th), general effects; 34 , Berridge, N. Am. J. of Hom., N. S., 5, p. 375, effects in self; 35 , same, in another man; 36 , same, in a girl; 37 , same, Am. Obs., 1875, p. 307, effects on self; 38 , Ostrom, Hahn. Month., 1875, p. 16, effects of a large amount, in a girl, aged nineteen.

MIND

• Became so violent in dentist's chair, could hardly hold her, 30.
• Unusual exaltation of mind, the most agreeable sensations and fancies; had an involuntary desire to laugh (after one hour), 13.
• "The principal feeling was a total difficulty of restraining my feelings, both corporeal and mental; or, in other words, not having any command over myself," 11.
• Begged me to give her something to kill her or else make her better, 30.
• Mental torture beyond endurance. It was a nightmare of the mind, pure and simple, in which no earthly objects took part. He was like Blake, or any other madman you might name, trying in that exquisitely painful moment to solve the insoluble and grasp the illimitable; he was now endeavoring to conceive what lay beyond all space, and now trying to realize the condition of nothing. Then came a spiral winding from an infinite distance into a point, when he exclaimed to himself, "I can bear it no longer; I am going mad," and at that instant awoke, 31.
• "Inhaling the gas, I felt as if every nerve was gently agitated with a lively enjoyment," 10.
• Soon found his nervous system agitated by the highest sensations of pleasure, but which were difficult of description. When the bags were exhausted and taken from him, he suddenly started from his chair, and vociferating with pleasure, made towards those that were present, as he wished they should participate in his feelings. He struck gently at Davy, and a stranger entering the room at the same moment, he made towards him and gave him several blows; but, he adds, it was more in the spirit of good humor than in that of anger. He then ran through different rooms in the house, and at last returned to the laboratory somewhat more composed, although his spirits continued more elevated for some hours after the experiment; he felt, however, no subsequent effects either in the evening or day following. Upon another occasion, he states that his sensations were superior to anything he ever before experienced; his step was firm, and all his muscular power increased. His nerves were more alive to every surrounding impression; he threw himself into several theatrical attitudes, and traversed the laboratory with a quick step, while his mind was elevated to a most sublime height; he says that it is giving but a faint idea of his feelings to say that they resembled those produced by a representation of a heroic scene on the stage, or by reading a sublime passage in poetry, when circumstances contribute to awaken the finest sympathies of the soul. The influence, however, of this inspiring agent appears to have been as transitory as its effects were vivid; for he afterwards observes, "I have seldom lately experienced vivid sensations. The pleasure produced by the gas is slight and tranquil, and I rarely feel sublime emotions or increased muscular power," .

Nothing exists but thoughts! The universe is composed of impressions, ideas, pleasures, and pains!

" About three minutes and a half only had elapsed during this experiment, though the time, as measured by the relative vividness of the recollected ideas, appeared to me much longer. Not more than half of the Nitrous oxide was consumed. After a minute, before the thrilling of the extremities had disappeared, I breathed the remainder. Similar sensations were again produced; I was quickly thrown into the pleasurable trance, and continued in it longer than before. For many minutes after the experiment, I experienced the thrilling in the extremities; the exhilaration continued nearly two hours. For a much longer time I experienced the mild enjoyment before described connected with indolence; no depression or feebleness followed. I ate my dinner with great appetite, and found myself lively and disposed to action immediately afterwards. I passed the evening in executing experiments. At night, I found myself unusually cheerful and active, and the hours between 11 and 2 were spent in copying the foregoing detail from the common place book, and in arranging the experiments. In bed, I enjoyed profound repose. When I awoke in the morning, it was with consciousness of pleasurable existence, and this consciousness, more or less, continued through the day, 6.

• A few seconds after the commencement of the inhalation the pulse began to grow firmer and less compressible, and to decrease in frequency, falling from 85 to 75 in the course of the first minute. In less than a minute the breathing became quicker and almost of a blowing character. He was somewhat exhilarated and stamped with his feet to show the satisfaction he felt. The breathing then assumed a labored, almost stertorous, character, and I attempted to remove the face-piece, but he clutched it firmly and resisted my efforts to do so not long, however, for he soon began to lose consciousness and his hold relaxed. On recovering, which was almost instantaneous after removal of the inhaler, he said he felt as if just aroused from a delicious sleep, 22.
• (The headache, which had troubled me during the afternoon and before going to sleep, was entirely gone, and I felt much invigorated by the effects of the gas), 17.
• It produced feelings analogous to those of intoxication. He was for some time unconscious of existence, but at no period of the experiment were his sensations agreeable; a momentary nausea followed, but unconnected with languor or headache. In a subsequent trial it would appear that he did experience certain thrillings that were highly pleasurable, 8.
• Sensations perfectly new and delightful, 12.
• The dilute gas has almost invariably an exhilarating effect upon me; for the first few seconds the symptoms resemble those caused by the pure gas, but come on more gradually. The breathing is at first affected, and frequently at the end of a minute is of a panting character. At this stage a slight sense of suffocation may be felt, soon passing off, however, not to return again as long as the supply of Nitrous oxide is abundant. The next symptom is a feeling of fulness in the head, and a tendency to fixedness of the eyes; then it soon becomes apparent that general sensibility is affected, the perception of external objects being slower. Next is noticed a sense of increased resistance in the feet, suggesting the idea that they might act involuntarily in throwing the body forward. These symptoms become more marked, and develop into unmistakable dizziness, more noticeable, of course, if the inhalant is standing, and then an effort is required to maintain the equilibrium. At this stage, too, are perceived the thrilling and vibratory sensations; the accommodating power of the eye is affected, and objects are seen as through a mist. The senses of smell and hearing become more acute; distant and otherwise faintly heard sounds are judged to be near, and are distinctly heard; if they are of a rhythmical kind, as the sounds of a mason's hammer, they seem to recur more frequently, and the appreciation of the rhythm is more acute. And now the more strictly mental symptoms come into prominence. Having on one occasion inhaled the gas when I had a rather severe headache, it was at this stage the sense of pain left me, after which it seemed to me there was an interval between the perception that the pain had given and that feeling of satisfaction which always follows sudden relief from suffering, and my mind began to busy itself with definitions of pleasure and pain; but this mood quickly changed to one of extreme self-confidence-recklessness as to every other consideration but that of having plenty of Nitrous oxide, and a general feeling of contempt for all metaphysical questions whatever. Ideas rushed in a disordered current through my mind, and delirium set in. It is at the commencement of this stage that the mind loses the power of discriminating between the appropriate and the ridiculous, and is preternaturally susceptible of receiving and being influenced by suggestions from without; and it is on the ideas and actions now initiated that the delicious intoxication turns. The ideas seem, as it were, to expand beyond the recognition of the mind, which at this point in its disordered activity also seems to vault over that interval which, in its normal condition, it recognizes to exist between the wish and its realization. Automatic acts succeed each other, or are repeated with great rapidity, and are performed in an exaggerated manner, the subject of the experiment shouting and gesticulating with the greatest vehemence should he wish to communicate any, even the most trivial thing, and often repeating the last word of a sentence many times, and each time in a louder key. I have endeavored to arrest the action of the gas in all stages of its operation, with a view of analyzing, if possible, the state of mind indicated by the confident belief that a great discovery has been made. When it is considered with what avidity the gas is inspired, and that it is necessary that the inhalation should be discontinued at the very moment when the enjoyment it is affording is at its height, and when all sense of prudence and responsibility seems to be annihilated, it will be understood how great are the difficulties in the way of success in such an attempt. On account of the delirium which always accompanies this condition I could never be certain, on recovering from the effects of the gas, that I had not passed through a short stage of unconsciousness, nor that the idea my mind has grasped, as being the last that had passed through it, was indeed the last. In the milder forms of delirium it has seemed to me as though consciousness kept ebbing and flowing. I feel sure, however, that in some instances I have been able to secure the receding thought and to retain it until the momentary confusion of mind had passed off. Two such instances I will describe. On one occasion I wanted to find out how much gas was being consumed in the experiment, and impressed on my mind the exceeding desirableness of learning this. On emerging from the state of delirium I found myself with uplifted hand in the act of striking my knee, to impress upon my memory the fact that I had refilled the inhaling bag; and I fancied that I either had shouted, or was upon the point of doing so, in a triumphant voice, "I have filled it again." The act by which I sought to emphasize the important observation was a repetition of a blow I had already given my knee, as there was still some feeling of it left, and I thought that it was due to this that I had so suddenly awaked to perfect consciousness. I found that I really had turned the key to admit more of the gas into the bag. Had I not came to myself at that moment, I have no doubt that in the next this trivial occurrence would have been magnified beyond recognition, and have left the feeling that I had discovered the secret of the universe. The second time, returning clearness of intellect found me vociferating, in a most triumphant tone of voice, and each time I fancied in a higher key, "Off, off, off." In this case the predominant idea, before the commencement of the experiment, had been that I should notice how, and in what time, I passed off into unconsciousness. Again, to show how susceptible to suggestion the mind becomes under the influence of Nitrous oxide, and how it takes up and exaggerates any activity, whether bodily or mental, and how great the tendency is to dwell on and intensify any process of thought or series of automatic acts, I may describe how I was affected by the gas on other occasions. I respired it standing, to notice whether this position would in any way incite to bodily activity. As soon as I felt the influence of the gas stealing over me I commenced gesticulating, and immediately noticed a strong tendency to repeat the same movements, which, though at first wholly voluntary, soon became automatic in character, and required an effort to stop them. Commencing to shuffle about my feet as if dancing, I quickly found myself going through the steps of a Scotch reel, the only dance I ever properly learned, and which I believed I had forgotten. Each step was made with more alacrity than the one before, until I found it impossible to maintain any degree of accurate adaptation of the inhaler to my face, and then the feelings of exhilaration died away. On almost immediately resuming the inhalation in the sitting posture, however, I passed into the delirious stage in a few seconds. I have found that, by imitating the contortions of face attendant upon crying or laughing, I can at will, at a certain stage in the operation of Nitrous oxide, induce a most uncontrollable paroxysm of either. The general propensity to laughter, I have thought, might be attributable, in some measure at least, to the fact that when the inhalation has been continued a certain length of time, convulsive contractions of the diaphragm always occur, which would, of course, initiate one very important movement in the automatic series accompanying laughter. The sense of hurry and tumultuous rushing of ideas through the mind may be exaggerated by, if it is not, in a great degree, due to, the furious panting which is commonly observed before delirium sets in, .

What an amazing concentration of ideas!

" I had no pleasurable feeling whatever; I used no muscular motion, nor did I feel any disposition to it; after a minute, when I made the note of the experiment, all the uncommon sensations had vanished; they were succeeded by a slight soreness in one of the arms and in the leg; in three minutes these affections likewise disappeared, 3. [30.]

• He remained perfectly quiet for nearly a minute, and when asked how he felt, said he was drowsy, and just going to sleep. He was told that he must keep awake. When he had respired the gas for nearly two minutes, and seemed indisposed to activity of any kind, he was told, in a loud voice, to get up, and asked if he was not ready to dance; at the same time he was seized by the arm as if to lift him from the chair. He immediately sprang to his feet, saying he was ready for anything, and began capering and swinging his arms about as though he had lost all control over his movements. He came to himself, however, in a few seconds, looked bewildered, and said he remembered nothing from the first few seconds after the commencement of the inhalation, 25.
• In the concentrated form it produces anæsthesia in so rapid and agreeable a manner, that there is only time to remark that the gas has a pleasant taste and odor; that it causes a sense of dimness to pass before the eyes, and gives rise to a sound as of rushing water in the ears, when all consciousness and power of volition are annihilated. The outward signs of its action, as seen by a spectator, do not make quite so agreeable an impression on the mind, for with the commencement of anæsthesia lividity of the face sets in. The muscles lose their tonicity; the jaws and lips fall asunder; the head droops, and the face assumes a besotted aspect. Generally, loud snoring accompanies inspiration, when the anæsthesia is very profound, though this is not always the case. When an unusually large quantity of the gas has been inhaled to produce anæsthesia, or when the gas has been in the slightest degree diluted with common air, convulsions may occur affecting the muscular system generally, though it is more common for only the muscles of one limb to be affected. Mr. Fox has noticed that violent twitchings often occur when young children are made to inhale the gas. The intermediate signs are, that the breathing becomes quicker in about twenty seconds after the commencement of inhalation; at the end of a minute, however, it becomes smaller again and less frequent. Complete anæsthesia is sometimes produced in less than a minute, but in the majority of cases the inhalation must be continued a minute and a half. When the administration is discontinued, recovery very rapidly takes place, the first feelings being like those one has on being suddenly awakened from an agreeable sleep; and on rising from the chair, there is, for a moment or two, a feeling of unsteadiness, together with slight confusion of ideas, and a tendency to stammering in speech. It is very rarely that any disagreeable after-effects are complained of, 26.
• The first inspiration, and, I may say, the first contact of the gas with the pulmonary membrane, produced a general sensation of numbness somewhat like sleepiness. On the second inspiration the sensation of numbness was decided; I seemed to see a gauze vibrating before the vision, similar to that observed from the influence of chloroform. On the third inspiration the numbness had made rapid progress, but intelligence remained, with perfect freedom of movement. I pricked my hand with a pin and found that sensibility was considerably diminished. After the fourth inspiration, I began to be separated from the external world; ideas were vague and exalted, yet I was quite able to prick my hand with a pin, but did not experience any sensation therefrom; the loss of sensibility, however, was not complete; I was conscious of contact like that of a blunt instrument; the gauze before the eyes was white and very brilliant, and the vibrations were very rapid, resembling persistent phosphorescence; I continued to assist in the experiment of which I was the subject. On the fifth inspiration I lost consciousness and fell into a profound sleep without troubled dreams; during this the inhaler was removed from my mouth without my being conscious of it, and after remaining in this condition for half an hour, I came to myself; the numbness disappeared very rapidly after inhaling pure air. After four or five inspirations the forehead was covered with perspiration. After the experiment I walked two kilometers without fatigue, and had a very good appetite; I had lost none of my activity during the remainder of the walk, only at night I felt more fatigued than usual, .

The shortest time was forty-five seconds, the longest two minutes thirteen seconds. Recovery is usually rapid and complete, the patient waking up as from a sleep. But it does sometimes happen, usually in young ladies between the ages of fourteen and twenty, that there is an intermediate stage between that of complete unconsciousness and recovery, when some excitement is exhibited, such as tossing about restlessly in the chair and weeping, they, on recovery, being generally very much surprised to find themselves so doing. Out of the above-mentioned cases, we have noted seven to have been affected in this manner in a greater or less degree; three complained of slight giddiness or faintness, and one was a little sick. One patient, a boy, urinated, his father having declined to indulge his expressed wish to do it before the operation. In several cases the removal of teeth was felt, but unattended with pain. The longest period during which we have noticed a patient to be insensible is one minute. In regard to the sensations experienced by patients, the majority are able only to say that they have been unconscious, save that they have been asleep and dreaming, the dreams being often pleasant, sometimes more like nightmare; and lastly, some complain that they have had considerable annoyance from rushing or singing noises in the head. One little girl was immensely pleased with it; she said that "she felt as if she was being tickled all over." Unconscious reflex screaming is not uncommon with children during the operation, but it does not seem to be connected with any particular form of dreaming, 28.

• Soon became insensible to physical pain, 31.
• A peculiar sensation of expansion, 14.
• For a week afterwards exceedingly unwell, feeling low and depressed, as if the whole nervous system had received a severe shock, 31.
• Rose in the morning very "seedy," as if he had just come off a sea-voyage, 31.

HEAD

• On going into open air, vertigo, with staggering to the left, 36.
• Decided dulness and almost dizziness of the head, 15.
• Giddiness after the palpitation, 34.
• A kind of waving of the head, 14. [50.]
• Numb feeling in head, spreading thence over the body, before the paroxysms, 30.
• Headache and aching along spine, as if they were asleep, 30.
• Headache after the return of consciousness, 34.

EYE, EAR, AND FACE

• Dilated pupils with the unconsciousness, 34.
• Eyeballs protruding, 29.
• On waking from the unconsciousness, voices of others seemed to proceed from a great distance, 35.
• On waking, voices seemed to come from a distance, or to be in a whisper, 36.
• He had to an excessive degree the livid countenance and blue lips so frequently noticed in administering this gas, 17a.
• Livid face with the unconsciousness, 34.
• Livid face, 36. [60.]
• Features puffy and swollen, 29.
• Blueness of the lips, ear, and face; afterwards, face dusky, 29.
• It needed great force to separate the jaws, 29.

MOUTH, THROAT, STOMACH, AND RECTUM

• Mouth and head feel numb, as though asleep, 30.
• The point of the tongue thrust between the teeth, 29.
• Weakness, and feeling of constriction in the throat, which interfered with deglutition (second day), 38.
• Pressure in the epigastrium, 30.
• Nausea, after the return of consciousness, 34.
• Vomiting, subsequent to the operation, from saliva running down the throat upon the epiglottis; he was of a bilious temperament, and the next day suffered some from bilious vomiting, 17a.
• (The hæmorrhoidal pains, from which the prover suffered, entirely disappeared), 13.

RESPIRATION, HEART, NECK AND BACK. [70.]

• Quick respiration, 36.
• Breathing thick and stertorous, 29.
• Suffocating feeling, 36.
• Palpitation of heart, afterwards felt and heard in head, 34.
• Tension in sides of neck, in region of carotids, 37.
• Drawing in neck, as though skin were contracted or cords shortened, 30.
• Sensation of drawing in the muscles, especially in the lumbar muscles, 13.

GENERALITIES AND FEVER

• Increased muscular rigor, 13.
• Loss of muscular power, 34.
• The account given by Dr. Kinglake agrees pretty much with those already cited. He adds, however, that the inspiration of the gas had the farther effect of reviving rheumatic irritations in the shoulder and knee-joints, which had not been previously felt for many months. Though much relieved of the pains, noticed when the effects were passing off, a momentary recurrence of rheumatic pains, not felt for some time before, and that a yellow area, caused by a leechbite, became, during inhalation, red and swollen, and the itching and tingling was so great as to cause a fear of suppuration, 9. [80.]
• General weakness and prostration, 39.
• Rather faint after the return of consciousness, 34.
• Fever every afternoon from 3 to 6, 30.
• Face covered with perspiration after the return of consciousness, 34.
• Coldness of feet and legs to the knees between the paroxysms of unconsciousness, 30.