When hypnotism made one of its periodic re-appearances in 1837, this time under the name of mesmerism, after that extraordinary exponent of its powers Mesmer, Simpson recognised in it a possible method for "casting the patient asleep" before operation and set to work to investigate its phenomena. A Frenchman named Du Potet, disheartened by the prejudice against mesmerism in his own country, came to London in 1837, and was fortunate enough to receive the support of Dr. John Elliotson, physician to University College Hospital. Elliotson's advocacy of the new practice was received with ridicule by the profession, and was treated with such scathing contempt by the _Lancet_ and other journals, that he was completely ruined. Simpson was very successful in his experiments with mesmerism, conducted on the lines suggested by Elliotson, but he recognised that, after all, it was not the agent for which he was seeking, and dropped his researches. He did not resume them even when Liston, a few years later, stimulated by the advocacy of the Manchester surgeon Braid, who met with a better reception than Elliotson, and by the relation of a long series of successful cases by a surgeon named Esdaile, in Calcutta, actually performed operations with success on patients brought under its influence. The first suggestion to produce anaesthesia by the _inhalation_ of drugs was made by Sir Humphry Davy in 1800. He discovered by experiment upon himself that the inhalation of _nitrous oxide_ gas--commonly known as a _laughing gas_--had the power of relieving toothache and other pains; he described the effect as that of "uneasiness being swallowed up for a few minutes by pleasures." Although he stopped short at this stage, and does not seem to have used the inhalation to produce actual loss of consciousness, he, nevertheless, forecast the future by suggesting that nitrous oxide might be used as an inhalation in the performance of surgical operations, in which "no great effusion of blood" took place. Some thirty years later Faraday pointed out that _ether_ had effects upon the nervous system when inhaled, similar to those of laughing-gas. These two drugs came to be inhaled more in jest than in earnest; more as an amusing scientific experiment for the sake of the pleasure-giving excitement they set up, than for the purpose Davy had suggested. Ether, it is true, was recommended even before Davy's day for the relief of the suffering in asthma, but until the fifth decade of the century no one had attempted to prevent suffering as inflicted by the surgeon or the dentist, by producing the state of unconsciousness brought about by the inhalation of such drugs as ether--a process now known to the world as anaesthesia.