Neither my notes nor my recollection supply much in addition to what I formerly stated in the Notice of Observations at the Pneumatic Institution. Longman. The gas maintains its first character as well in its effects on me, as in the benefit it confers on some of the paralytic, and the injury it does or threatens to the hysterical and the exquisitely sensible. I find that five or six quarts operate as powerfully as ever. I seem to make a given quantity go farther by holding my breath so that the gas may be absorbed in a great degree without returning into the bag, and therefore, be as little heated before inspiration as possible.—This may be fancy.
After innumerable trials, I have never once felt lassitude or depression[226]. Most commonly I am sensible of a grateful glow circum præcordia. This has continued for hours.—In two or three instances only has inhalation failed to be followed by pleasurable feeling, it has never been followed by the contrary. On a few occasions before the gas was exhausted, I have found it impossible to continue breathing.
The pulse at first becomes fuller and stronger. Whenever, after exposure to a cold wind, the warmth of the room has created a glow in the cheeks, the gas has increased this to strong flushing—which common air breathed in the same way, failed to do.
Several times I have found that a cut which had ceased to be painful has smarted afresh, and on taking two doses in succession, the smarting ceased in the interval and returned during the second respiration. I had no previous expectation of the first smarting.
The only time I was near rendering myself insensible to present objects by very carefully breathing several doses in quick succession, I forcibly exclaimed, TONES!—In fact, besides a general thrilling, there seemed to be quick and strong alterations in the degree of illumination of all surrounding objects; and I felt as if composed of finely vibrating strings. On this occasion, the skin seemed in a state of constriction and the lips glued to the mouth-piece, and the mucous membrane of the lungs contracted, but not painfully. However, no constriction or corrugation of the skin could be seen. I am conscious of having made a great number of observations while breathing, which I could never recover.
Immediately afterwards I have often caught myself walking with a hurried step and busy in soliloquy. The condition of general sensation being as while hearing chearful music, or after good news, or a moderate quantity of wine.
Mr. John Cave, Junr. and his three friends, as well as others, compared the effects to Champagne. Most persons have had the idea of the effect of fermented liquors excited by the gas. It were to be wished that we had, for a standard of comparison, observations on the effect of these liquors as diversified and as accurate as we have obtained concerning the gas; nor would more uniformity in the action of these substances be observed if the enquiry were strictly pursued. Opium and spirits seem, in particular states to sicken and distress in the first instance; how differently does wine at an early hour and fasting act upon those who are accustomed to take it only after dinner!
I thought it might be an amusing spectacle to see the different tints of blood flowing from a wound by a leech in consequence of breathing different airs. The purple from the nitrous oxide was very evident. Oxygene, we thought, occasioned a quicker flow and brighter color in the blood. In another experiment, an inflamed area round the puncture from a leech applied the day before, was judged by several spectators to become much more crimson on the respiration of about 20 quarts of oxygene gas, which possibly acts more powerfully on inflamed parts.[227] These and many similar experiments, require to be repeated on the blood of single arteries opened in warm and cold animals.
It has appeared to me that I could hold my breath uncommonly long when respiring oxygene gas mixed with nitrous oxide. While trying this to-day, (17th June), I thought the sense of smell much more acute after the nitrous oxide than before I began to respire at all; and then I felt conscious that this increased acuteness had before repeatedly occurred—a fact very capable, I apprehend, of a pneumatological interpretation.
Time by my feelings has always appeared longer than by a watch.