Anaesthetics Antient and Modern

THE NITROUS OXIDE ERA

Although, as already stated, Humphry Davy had discovered the anæsthetic properties of nitrous oxide as far back as the year 1800, forty-four years elapsed before his idea was put into practical use.

[Sidenote: Colton lectures on nitrous oxide]

On December 11th, 1844, Dr. G. Q. Colton, a well-known lecturer on popular scientific subjects in America, and a pupil of Professor Turner, of London, delivered a lecture at Hartford, Connecticut, during which he gave a demonstration of the action of nitrous oxide gas. Horace Wells, a dentist, then in practice in the same town, formed one of the audience.

[Illustration: HORACE WELLS]

[Sidenote: Wells makes his historic experiment]

Among the persons who were invited by the lecturer to inhale the gas for the amusement of the audience was a man named Cooley, who wounded himself severely by falling against the benches, and only became aware of the fact when he saw the blood. Wells was greatly struck by this incident, and he determined to test the anæsthetic effects of the gas upon himself the next day by having a decayed upper molar extracted while under its influence. After the lecture he asked Dr. Colton if he would come to his house and administer the gas to him; and, on receiving his promise, he induced a Dr. Riggs to be the operator.

The historic event is described by the latter as follows: “A few minutes after I went in, and, after conversation, Dr. Wells took a seat in the operating chair. I examined the tooth to be extracted, with a glass, as I usually do. Wells took a bag of gas from Dr. Colton and sat with it in his lap, and I stood by his side; he then breathed the gas until he was much affected by it: his head dropped back, I put my hand to his chin, he opened his mouth, and I extracted the tooth. His mouth still remained open some time. I held up the tooth with the instrument that the others might see it; they, standing partially behind the screen, were looking on. Dr. Wells soon recovered from the influence of the gas so as to know what he was about, discharged the blood from his mouth, and said, ‘A new era in tooth-pulling!’ He said it did not hurt him at all. We were all much elated, and conversed about it for an hour later.”

[Illustration: “A NEW ERA IN TOOTH-PULLING” The first dental operation performed on Horace Wells whilst under the influence of nitrous oxide gas]

[Sidenote: “A new era in tooth-pulling”]

After this, Wells extracted several teeth from his patients under nitrous oxide gas with equal success, and then went to Boston in order to make his discovery known to the medical profession in that city. He remained there some days in the hope of being allowed to try the gas in a case of amputation in the Massachusetts General Hospital, but the experiment was postponed. Dr. Warren, senior surgeon to the institution, however, invited him to address his class on the subject of anæsthesia, after which he was asked to administer the gas in a case of tooth extraction. He was assisted on this occasion by Morton, a Boston dentist who had been his pupil, and afterwards, for a time, his partner. The experiment, as Wells himself confesses, was not quite a success, the gas-bag having been removed too soon. The whole thing was denounced as a piece of humbug, and Wells was hissed out of the room as an impostor.

[Sidenote: Wells disheartened by failure]

[Sidenote: The death of Horace Wells]

Disheartened at length by the failure of his repeated attempts to establish his claims to priority as the discoverer of anæsthesia, his mind appeared to become affected, and for a time he wandered about the streets of New York. On January 4th, 1848, he was arrested and charged with throwing vitriol, but while in gaol he opened his radial artery, having first inhaled ether to make death painless. This sad event closed, at the age of thirty-two, the career of Horace Wells, to whom at least belongs the credit of having first shown the practicability of producing insensibility by nitrous oxide, and of having thus, in his own words, “established the principle of anæsthesia.”

THE ETHER EPOCH

Probably the first published account of the use of ether as a medicinal agent was made by Morris in a letter read before the Society of Physicians in London,[1] on December 18th, 1758, in which he advocates its use internally, and also as an external application.

[1] “Med. Obs. and Enq.” by the Society of Physicians in London, vol. 2, page 176, 1764.

In 1818, Faraday, as already stated, had called attention to the anæsthetic properties of ether, and showed that the vapour of sulphuric ether, when inhaled, produced effects similar to those of nitrous oxide. After Wells’ failure at Boston nothing further seems to have been done for a time to investigate the use of nitrous oxide as an anæsthetic.

[Sidenote: Early experiments with ether]

In 1839, William E. Clarke, a young medical student of Rochester, New York, was in the habit of amusing some of his friends, among whom was another student named W. T. G. Morton, by the inhalation of ether. Emboldened by his experiences, in 1842 he is said to have administered ether, by means of a towel, to a young woman named Hobbie, and during the period of insensibility which followed, one of her teeth was extracted by a dentist named Elijah Pope.

J. Marion Sims relates the following incident which he states happened in the year 1839:--“A number of youths in Anderson, South Carolina, were exhilarating themselves one day with the seductive vapour of ether. In their excitement they seized a young negro who was watching their antics, and compelled him to inhale the drug from a handkerchief which they held over his mouth and nose by main force. At first his struggles only added to the amusement of his captors, but they soon ceased as the boy became unconscious, stertorous and apparently dying. After an hour or two of anxiety on the part of the spectators he, however, revived, and was apparently no worse for his alarming experience.”

[Sidenote: Long claims to have used ether in 1842]

Three years after this incident one of the participators in the affair, named Wilhite, became the pupil of Dr. Crawford W. Long, a physician then practising in Jefferson, Jackson County, Georgia. Both the doctor and his pupils used occasionally to amuse themselves by inhaling ether, and the former often noticed that while thus excited he was insensible to blows and bruises. Wilhite recounted to him his memorable experience with the negro boy; and, in March, 1842, Long is said to have persuaded a patient, on whom he was about to operate for a small encysted tumour, to inhale ether until he was insensible. The patient consented, and the tumour was removed without any pain or accident. This memorable event was simply recorded by Long in his ledger thus:--“James Venable, 1842. Ether and excising tumour, $2.00.” Three months later he removed another tumour from the same patient in a similar way, and also performed three other operations during that year. He is said to have again repeated the experiment in 1843 and 1845, but the district in which he lived was so far removed from contact with the large cities and centres of thought, that the discovery remained unknown and unpublished until long after the anæsthetic properties of ether had been fully proved elsewhere. Long himself admits that he considered ether impracticable owing to the shortness of the anæsthetic state, and he therefore abandoned its use.

[Sidenote: Marcy’s experiment]

Towards the end of the year 1844, Dr. E. E. Marcy, a surgeon of Hartford, is said to have administered ether to a patient, and to have removed an encysted tumour about the size of a walnut from the scalp.

It is stated that Horace Wells was present at this operation, which was quite successful, but, being warned that ether was dangerous to life, the experimenters abandoned its use in favour of nitrous oxide gas.

[Sidenote: Morton’s experiments with ether]

In 1846, W. T. G. Morton (referred to previously) who had been in partnership with Wells as a dentist, and assisted him in the unfortunate experiment with nitrous oxide in Boston, now directed his attention to the finding of a more suitable anæsthetic for painless operations in dental surgery. After many unsuccessful attempts with various narcotics, Charles T. Jackson, a chemist of Boston, whose pupil he had been, suggested that he should try sulphuric ether, the properties of which had been known for so long.

[Illustration: CHARLES T. JACKSON]

[Sidenote: Jackson’s story]

It was about the end of September, 1846, that Jackson states he informed Morton that he had experimented on himself by inhaling ether on a folded towel. He found that he lost all power over himself, and fell back in his chair in a state of curious sleep. Morton, however, tells another story, and relates how, having procured some chemically pure ether on September 30th, 1846, he shut himself in a room alone and inhaled the vapour. He states: “I found the ether so strong that it partly suffocated me, but produced no decided effect. I then saturated my handkerchief and inhaled it from that. I looked at my watch and soon lost consciousness. As I recovered I felt a numbness in my limbs, and a sensation like nightmare. I thought for a moment I should die in that state, but at length I felt a slight tingling of the blood in the end of my third finger, and made an effort to press it with my thumb, but without success. At the second effort I touched it, but there seemed to be no sensation. I attempted to rise from my chair, but fell back, and looked immediately at my watch and found that I had been insensible between seven and eight minutes.”

THE FIRST DENTAL OPERATION UNDER ETHER

Morton soon had an opportunity of making a practical experiment with the anæsthetic, for the same evening, about nine o’clock, a man named E. H. Frost called upon him suffering from a violent attack of toothache. “Can’t you mesmerise me?” asked the sufferer. “Upon which,” says Morton, “I told him that I had something better than mesmerism by means of which I could take out his tooth without giving him pain. He gladly consented, and saturating my handkerchief with ether, I gave it to him to inhale. He became unconscious almost immediately. It was dark, and Dr. Hayden held the lamp. My assistants were trembling with excitement, apprehending the usual prolonged scream from the patient while I extracted a firmly-rooted bicuspid tooth. I was so agitated that I came near throwing the instrument out of the window. But now came a terrible reaction. The wrenching of the tooth had failed to rouse him in the slightest degree. I seized a glass of water, and dashed it in the man’s face. The result proved most happy. He recovered in a minute, and knew nothing of what had occurred.”

[Sidenote: First surgical operation under ether]

Morton next appealed to Dr. John C. Warren, who was then Senior Surgeon at the Massachusetts General Hospital, and obtained permission to test his new anæsthetic on a patient about to undergo a surgical operation. The date fixed was Friday, October 16th, 1846, and at the appointed time a large number of medical men had assembled in the theatre. Morton administered the anæsthetic successfully, and the operation, which was for a congenital vascular tumour of the neck, in a young man named Gilbert Abbot, was completed in about five minutes without a groan from the patient. When it was finished, Dr. Warren exclaimed: “Gentlemen, this is no humbug!” The interest excited amongst those who witnessed the operation was naturally very great, and Dr. Henry J. Bigelow, who was present, said to a friend whom he met later in the day: “I have seen something to-day that will go round the world!” His prophecy proved correct.

Up to this time Morton had not disclosed the nature of the agent he employed, and nothing more was done until November 7th, when he expressed his willingness to reveal the secret. On this date two major operations were performed under ether, one by Dr. Hayward and the other by Dr. Warren.

From this time ether took its place as a general anæsthetic, and the practice of anæsthesia was firmly established.

[Sidenote: The origin of the words “anæsthesia” and “anæsthetic”]

Soon after the memorable 16th of October, a meeting was held in Boston, to choose a name for the new anæsthetic agent, and the word “letheon” was chosen by Morton himself; but, subsequently, Dr. Oliver Wendell Holmes suggested the name “anæsthesia” for the condition, and “anæsthetic” for the agent, which names have since come into general use.

Although it has never been very clearly established whether Morton or Jackson was the prime originator of the use of ether as an anæsthetic, the former was recognised by the United States Government as the discoverer, and received from it a handsome award. It seems most probable that Jackson supplied the inspiration, while Morton practically demonstrated it.

[Illustration: W. T. G. MORTON]

In reviewing the steps which led up to the discovery, it must not be forgotten that both Morton and Jackson were after all but followers of Collier, who first rendered himself unconscious with ether in the laboratory of University College, London, and forged one of the most important links in the chain of development.

Morton spent most of the remainder of his life in disputes about priority, and in efforts to secure recognition. He died bankrupt and broken-hearted on July 15th, 1868, before he had completed his forty-ninth year.

Curiously enough, Jackson, like Wells, became insane, and died in an asylum in 1880. When the friends of the rival claimants of the discovery of anæsthesia were proposing that monuments should be erected to each, Oliver Wendell Holmes characteristically suggested that all should unite in erecting a single memorial, with a central group symbolising painless surgery, a statue of Jackson on one side, a statue of Morton on the other, and the inscription underneath:--

TO E(I)THER

The news of the “ether process for removing pain,” as it was then called, spread rapidly. A private letter from Dr. J. Bigelow to Dr. Francis Boote, of Gower Street, carried the first news to England, and was communicated to the medical profession in London on December 17th, 1846. Two days later, Mr. James Robinson, a dentist, of Gower Street, performed the first dental operation under ether in England, the patient being a Miss Lonsdale, and the operation the extraction of a firm molar tooth.

On December 21st the first surgical operation under the new anæsthetic in England was performed by Robert Liston, in University College Hospital, London.

[Sidenote: First surgical operation under ether in Great Britain]

In the operating theatre, thronged with students, were the late Sir John Erichsen, the present Lord Lister, and many other famous surgeons. Mr. Barton relates an amusing incident which happened prior to the operation. Before the patient was brought in, the anæsthetist asked the students who crowded the benches in the theatre from floor to ceiling for some volunteer who would submit himself to be anæsthetised. A young man, Sheldrake, of very powerful build and a good boxer, at once offered to take the new anæsthetic, and came into the arena. “He lay on the table, and the anæsthetist proceeded to administer the ether. After the administration had proceeded for about half a minute, the subject of the experiment suddenly sprang up and felled the anæsthetist with a blow, and, sweeping aside the assistants in the arena, sprang shouting up the benches, scattering the students, who fled like sheep before a dog. He fell at the top bench, where he was seized and held down till he regained his senses. The whole scene hardly occupied a minute.”

[Illustration: An apparatus called “Letheon” One of the earliest employed for the administration of Ether]

[Sidenote: New method of administration]

Before operating, Liston addressed a few words to those present as to the nature of the experiment about to be tried. The ether was administered by Mr. William Squire in an apparatus he had devised, which consisted of a large bell-shaped receiver containing the ether, to which was attached a long tube and mouthpiece. The patient, a middle-aged man, who was suffering from malignant disease of the skin and tissues of the calf of the leg, for which amputation of the thigh was deemed necessary, passed easily into complete insensibility, and Liston rapidly removed the thigh, the cutting operation being declared to have lasted only thirty-two seconds. In a few moments the patient completely recovered consciousness, and apparently did not know that the limb was off. When the towel was removed from the uplifted stump so that he could see it, he burst into tears and fell back on his pillow. Both surgeon and patient were much affected, and the scene in the theatre was most impressive. All appeared to see what an incalculable boon was in store for the human race, and Liston could scarcely command his voice sufficiently to speak.

[Sidenote: A story of Liston]

Some amusing stories are related of Liston, who was a very big, powerful man. His fine physique was often useful in the pre-anæsthetic days, when a patient’s nerve gave way at the last moment at the sight of the crowded theatre and the operating-table with its straps. It is said that on one occasion a patient, losing his courage at the last moment, rushed shrieking down the long corridor of the hospital, with Liston at his heels. The man locked himself in a room, but the surgeon with his shoulder broke in the door, and half-dragged half-carried the poor wretch back to the operating theatre, where the operation for stone was successfully performed.

[Sidenote: First surgical operation under ether in Scotland]

The practice of using ether was soon followed in other hospitals, and not only medical men but distinguished laymen crowded to witness its use. In Scotland, Dr. Moses Buchanan, Professor of Anatomy in Anderson’s University, was the first to have news of the event, and immediately after his lecture that day he experimented with ether inhalation. On the following day, in the operating theatre of Glasgow Royal Infirmary, a patient was placed under the anæsthetic and successfully operated on for fistula. So rapidly, indeed, did the practice spread from one centre to another, that by the end of the first quarter of 1847 the use of the new anæsthetic may be said to have become general in all operation cases.

[Sidenote: Simpson proves value of ether in midwifery]

The value of ether in midwifery practice still remained to be proved, and Sir James Simpson was the first to suggest and test its use in this department. On January 9th, 1847, he first administered ether to a patient in order to facilitate the operation of turning. The result, he reported, was most satisfactory and important, for it at once afforded evidence of the one great fact upon which the whole of the practice of anæsthesia in midwifery is founded, viz., that though the physical sufferings of the patient could be relieved by the inhalation of ether, yet the muscular contractions of the uterus were not interfered with.

THE DISCOVERY OF CHLOROFORM AS AN ANÆSTHETIC

The next epoch-making event in the history of anæsthesia was the discovery of the anæsthetic properties of chloroform. The substance itself had been known for over a quarter of a century. Thomson, in his “System of Chemistry,” 1820, describes a liquid which is formed by the union of chlorine and olefiant gas, called “Dutch liquid,” or chloric ether. Early in the year 1831, Samuel Guthrie of Brimfield, Massachusetts, who was then residing in Sackett’s Harbour, New York State, in consequence of a statement that he had read that the alcoholic solution of this chloric ether was useful in medicine as a diffusible stimulant, devised an easy method of preparing it. This being done, he wrote an article which he entitled “A Spirituous Solution of Chloric Ether,” and forwarded it to the editor of the “American Journal of Science and Art,” in which it was published in October of the same year. In this article he fully describes his method of preparation. A few months later, in January, 1832, Soubeiran published a paper in a French journal, stating that he had discovered this method in 1831, and to the distilled fluid he produced he had given the name of “bichloric ether,” the formula being CHCl. Still a third claimant to the discovery came forward in the person of Liebig, who published his account in November, 1831, six months after Guthrie’s manuscript was in the publisher’s hands, and one month after its publication. The formula which Liebig deducted from his analysis was C{4}Cl{5}, and he called his product “chloride of carbon.” Although there may be some doubt as to which of these claimants was actually the first to manufacture the liquid, it is clear that Guthrie was the first to publish the account of the discovery. He was born in 1782, was a surgeon in the United States Army in 1812, and died in 1848.

From an account given by D. B. Smith, of Philadelphia, in the “Journal of the College of Pharmacy”[2] in 1832, there can be little doubt that the liquid first made by Guthrie was a fairly pure chloroform. He describes it in the following words: “The action of this ether on the living system is interesting, and may hereafter render it an object of importance in commerce. Its flavour is delicious, and its intoxicating properties equal to or surpassing those of alcohol.” In 1834, Dumas examined the liquid as prepared by Soubeiran, and declared that he had not obtained it pure, and further, that Liebig had made an error in its composition. On further research, Dumas gave the liquid the name of “chloroform,” and first worked out the real formula, C{2}HCl{3} (or, using the present system of atomic weights, CHCl_{3}).

[2] Now the “American Journal of Pharmacy”

[Sidenote: Previous use of chloroform in medical practice]

Although its narcotising properties were known to some extent, no one who used it at that time seems to have conceived the idea of fully testing its properties. In 1831, Ives, of Newhaven, treated a case of difficult respiration by actual inhalation of the vapour, and published the facts in “Silliman’s Journal” in January, 1832. Four years later, Dr. Formby, of Liverpool, prescribed it in hysteria; and Tuson, of London, employed it in the treatment of cancer and neuralgia in 1844.

[Sidenote: Simpson’s investigations]

The fact that one or two deaths had been attributed to the use of ether about this time, caused many workers to make a search for other agents with similar properties. Foremost among these investigators was Dr. James Young Simpson, Professor of Midwifery in the University of Edinburgh, who personally experimented with several chemical liquids in the hope of finding something less disagreeable and persistent in smell than ether.

[Illustration: DAVID WALDIE]

[Sidenote: Waldie suggests the use of chloroform]

About this time, Jacob Bell, a chemist, and a founder of the Pharmaceutical Society, published a suggestion that chloric ether should be used for inhalation instead of sulphuric ether; but his suggestion was apparently never put into practice. In October, 1847, Waldie, a chemist of Liverpool, was visiting Edinburgh, and in conversation with Professor Simpson, suggested to the latter the use of chloroform. He recommended the Professor to try it as an anæsthetic, and promised to make and send him some on his return to his home in Liverpool.

[Illustration: SIR JAMES YOUNG SIMPSON]

It appears to have been in that city that the drug was first introduced and probably first used in England as a medicinal agent. Waldie states that about the year 1838 a prescription was brought to the Apothecaries’ Hall, Liverpool (where he held the position of manager), of which one of the ingredients was chloric ether. The preparation was at that timen apparently not known in this country, for Dr. Brett, the chemist of the Company, specially prepared some from the formula he found in the United States Dispensatory. Its properties pleased some of the medical men, particularly Dr. Formby, by whom it was introduced into local practice. Waldie, finding that the preparation was not uniform in strength, improved the process by separating and purifying the chloroform, and dissolving it in pure spirit, by which a product of sweet flavour was obtained.

[Sidenote: On the eve of the great discovery.]

There seems little doubt that Waldie was the first to suggest the use of chloroform, as an anæsthetic, to Professor Simpson, who at once resolved to try it by experimenting on himself and his assistants. He made the first experiment in his own house on November 4th, 1847, and in a letter written to Waldie thus describes the event: “I am sure you will be delighted to see part of the good results of our hasty conversation. I had the chloroform for several days in the house before trying it, as, after seeing it such a heavy, unvolatile-like liquid, I despaired of it, and went on dreaming about others. The first night we took it, Dr. Duncan, Dr. Keith and I all tried it simultaneously, and were all ‘under the table’ in a minute or two.” Professor Miller, who was a neighbour of Simpson’s, used to come every morning to see if the experimenters had survived! He describes how, “after a weary day’s labour, Simpson and his assistants sat down and inhaled various drugs out of tumblers, as was their custom. Chloroform was searched for and found beneath a heap of waste paper, and with each tumbler newly charged the inhalers resumed their occupation. . . . A moment more, then all was quiet; then a crash. On awakening, Simpson’s first perception was mental. ‘This is far stronger and better than ether,’ said he to himself. His second was to note that he was prostrate on the floor, and that among the friends about him there was both confusion and alarm. Of his assistants, Dr. Duncan he saw snoring heavily, and Dr. Keith kicking violently at the table above him. They made several more trials of it on that eventful evening, and were so satisfied with the results that the festivities did not terminate until a late hour.”

[Sidenote: Simpson achieves success]

On November 10th, 1847, Simpson communicated his discovery to the Medico-Chirurgical Society of Edinburgh, in a paper entitled, “Notice of a new anæsthetic agent as a substitute for sulphuric ether.” A day or two afterwards an arrangement was made with Simpson to administer the new anæsthetic to a patient who was about to be operated upon, but, owing to some cause, he was unable to be present. The operation went on without him, and the patient died on the first incision of the knife. Simpson’s absence was providential indeed, for it saved the reputation of chloroform at the outset. On November 15th, chloroform was used for the first time in a surgical operation in the Edinburgh Royal Infirmary. Three patients were operated on successfully under its influence. One, who was a soldier, was so delighted with the effect that, on awaking after the operation, he is said to have seized the sponge with which administration had been made, and, thrusting it into his mouth, again resumed inhalation more vigorously than before.

To Simpson, there is no doubt, belongs the merit of having made anæsthesia triumph over all the opposition, which was at first, actively, offered to its use. For this he well deserved the rewards which fell upon him in the evening of his life.

Among those who aided in the establishment of the use of anæsthetics, mention must be made of the work of John Snow, who by his researches placed the practice on a scientific basis.

The advent of chloroform gave an impetus to other investigators in the field of anæsthesia, and during the last fifty years many other bodies have been introduced and tried with more or less success for the same purpose. Methyl chloride, which was discovered by Dumas and Peligot, was introduced by Deboe in 1887, who used it extensively in local affections. In 1867, Sir B. W. Richardson introduced methyl bichloride or methylene [methylene dichloride]. He formed a very high estimate of its properties as a good general anæsthetic, and said he preferred it for many reasons to chloroform, as he found that the anæsthetic sleep was produced more quickly and was more prolonged.

Sir T. Spencer Wells also advocated its use, and stated, in 1872, that it had fewer drawbacks than any then known anæsthetic. Tetra-chloride of methyn [carbon tetrachloride], which much resembles chloroform, was discovered by Regnault in 1839, and its anæsthetic properties were first made known by Sansom and Harley in 1864. Simpson was of the opinion that it had a more depressing effect upon the heart than chloroform, and was more dangerous generally as an anæsthetic.

Nunneley, of Leeds, also contributed work of value in this department of research, and introduced ethyl bromide and chloride of carbon. He dispelled the idea, long prevalent, that anæsthetics could be found only in a limited class of chemical compounds.

Among other substances which have been introduced during the last twenty-five years, but which, owing to one defect or another, have since been practically abandoned, mention should be made of butylic hydride [butane], ethylene, amylene, ethyl nitrate, aldehyde (introduced by Poggiale), carbon bisulphide, ethidene dichloride [ethylene dichloride] (discovered by Regnault and first used as an anæsthetic by Snow), and ethyl bromide, first prepared by Serullus in 1827.

LOCAL ANÆSTHETICS

Local anæsthesia, already alluded to as probably the earliest form of numbing sensibility to pain, was practised in antient times by the inunction of various narcotics, but after the seventeenth century the practice seems to have almost entirely gone out of use. The latter end of the nineteenth century, however, marks a new era in this department.

On September 15th, 1884, considerable interest was aroused by a communication made at the Ophthalmological Congress at Heidelberg, by Karl Koller, of Vienna, in which he demonstrated the effects of cocaine as a local anæsthetic.

[Sidenote: The discovery of Cocaine]

The alkaloid now known as cocaine was isolated by Gädeke, from the leaves of the Erythroxylon Coca as far back as 1855. He called it ethroxylene. Four years later a further investigation of the plant was made by Nieman, who noticed that the leaves produced a numbness of the tongue; and in 1874 Hughes Bennett demonstrated that cocaine possessed anæsthetic properties. In 1880, Von Anrep, who made a careful investigation of the drug, hinted that the alkaloid might be of use in general surgery as a local anæsthetic, and Koller undertook a series of experiments on animals in the laboratory of Professor Stricker, in which he found that complete anæsthesia of the eye, lasting, on an average, ten minutes, followed the introduction of a two per cent. solution of the alkaloid.

The immense value of such an anæsthetic in ophthalmic operations was universally recognised, and it at once came into general use. In painful conditions of mucous surfaces, and for minor operations, cocaine has been found of great service, and as a local anæsthetic it has a large field of usefulness. Since the introduction of cocaine, other substances have been brought forward, which, after extensive trials, have proved to be of real clinical value. Of these may be mentioned eucaine, a synthetic product (benzoyl-vinyl-diaceton-alkamine) discovered by Merling, and first studied by Vinci in Liebreich’s laboratory. Of the two forms of this drug used, which are known as A and B, the latter was soon found to be the only one suitable for producing local anæsthesia. Its properties are similar to those of cocaine, with the exception that it produces no vaso-constriction, and it is claimed that it is equal in anæsthetic power, whilst its toxicity is very much less.

[Sidenote: Stovaine and Tropa-cocaine]

Stovaine, or benzoyl-ethyl-dimethylaminopropanol hydrochloride, more recently introduced, is a synthetic product elaborated by Fourneau, and derived from tertiary amyl alcohol. It is much less toxic than cocaine, but its comparative value still remains to be proved by further trial. Tropa-cocaine, a drug closely allied to cocaine, and derived from the leaves of the Java coca plant, has recently been much used in Germany, but it does not appear to possess any advantages over cocaine or eucaine.

Novocaine, or para-amido-benzoyl-diethylamino-ethenol hydrochloride, has lately been found to possess satisfactory properties as a local anæsthetic in dental operations. It is said to be free from the toxic and local irritant action common to other local anæsthetics.