On this subject, we have lately acquired additional facts.
Miss E. a young lady who had been subject to hysteric fits, breathed three quarts of nitrous oxide mingled with much common air, and felt no effects but a slight tendency to fainting. She then breathed four quarts of pure nitrous oxide: her first inspirations were deep, her last very feeble. At the end she dropt the bag from her lips, and continued for some moments motionless. Her pulse which at the beginning of the experiment was strong, appeared to me to be at this time, quicker and weaker. She soon began to move her hands and talked for some minutes incoherently, as if ignorant of what had passed. In less than a quarter of an hour, she had recovered, but could give no account of her sensations. A certain degree of languor continued through the day.
A young lady who never had hysterical attacks, wished to breathe the gas. I informed her of the disagreeable effects it had sometimes produced, and advised her if she had the slightest tendency to nervous affection, not to make the trial. She persisted in her resolution.
To ascertain the influence of imagination, I first gave her a bag of common air, which she declared produced no effect. I then ordered for her a quart of nitrous oxide mingled with two quarts of common air; but from the mistake of the person who prepared it, three quarts of nitrous oxide were administered with one of common air. She breathed this for near a minute, and after the experiment, described her sensations as unpleasant, and said she felt at the moment as if she was dying. The unpleasant feelings quickly went off, and a few minutes after, she had apparently recovered her former state of mind. In the course of the day, however, a violent head-ache came on, and in the evening after she had taken a medicine which operated violently, hysterical affections were produced, followed by great debility. They occasionally returned for many days, and the continued weak and debilitated for a great length of time.
Mrs. S. a delicate lady, liable to nervous affections who had heard of the cases just detailed, chose to breathe the gas. By three quarts she was thrown into a trance, which lasted for three or four minutes. On recovering, the could give no account of her feelings, and had some languor for half an hour afterwards.
These phænomena have rendered us cautious in administering the gas to delicate females. In a few instances however, it has been taken by persons of this class, and even by those inclined to hysterical and nervous complaints with pleasurable effects.
Miss L. a young lady who had formerly had hysterical fits, breathed a quart of nitrous oxide with three quarts of common air without effects. Two quarts of nitrous oxide with one of common air produced a slight giddiness; four quarts of nitrous oxide produced a fit of immoderate laughter, which was succeeded by slight exhilaration, her spirits were good throughout the day, and no depression followed.
Miss B. Y—— and Miss S. Y—— both delicate but healthy young ladies, were affected very pleasantly; each by three quarts of nitrous oxide, the first time of respiring it. Miss B Y—— continued exhilarated and in high spirits for some hours after the dose. Miss S. Y—— had a slight head-ache, which did not go off for some hours.
Mrs. F. inclined to be hysterical, breathed four quarts of nitrous oxide mingled with common air. She was giddy and described her feelings as odd; but had not the slightest languor after the experiment.
III. Observations on the effects of Nitrous Oxide,
by Dr. Beddoes.