I made a discovery yesterday which proves how necessary it is to repeat experiments. The gaseous oxide of azote is perfectly respirable when pure. It is never deleterious but when it contains nitrous gas. I have found a mode of obtaining it pure, and I breathed it to-day in the presence of Dr. Beddoes and some others--sixteen quarts of it for near seven minutes. It appears to support life longer than even oxygen gas, and absolutely intoxicated me. Pure oxygen gas produced no alteration in my pulse nor any other material effect, whereas this gas raised my pulse upwards of twenty strokes, made me dance about the laboratory as a madman, and has kept my spirits in a glow ever since. * * * * * Yours, with affection and respect, HUMPHRY DAVY. Dr. Paris says Coleridge gave him this account of of the caution of Davy at this time: Dr. Beddoes thought nitrous oxide gas would cure paralysis. A patient was to be treated by Davy. He first took the temperature by means of a small thermometer placed under the tongue. The patient immediately declared that he felt better. The opportunity was too tempting to be lost. Davy cast an intelligent glance at Mr. Coleridge, and desired the patient to renew his visit on the following day, when the same ceremony was again performed, and repeated every succeeding day for a fortnight, the patient gradually improving during that period, when he was dismissed as cured, no other application having been used than that of the thermometer. Southey thus wrote his opinion and that of Coleridge regarding Davy at this time: ‘He is a marvellous young man, whose talents I can only wonder at.’ Later he wrote: My residence at Westbury was one of the happiest portions of my life.... I was in habits of the most frequent and intimate intercourse with Davy, then in the flower and freshness of his youth. We were within an easy walk of each other over some of the most beautiful ground in that beautiful part of England. When I went to the Pneumatic Institution he had to tell me of some new experiment or discovery and of the views which it opened for him, and when he came to Westbury there was a fresh portion of Madoc for his hearing. On July 3, 1800, Davy wrote from Bristol to Gilbert: