I had never heard of the effects of the nitrous oxide, when I breathed
six quarts of it. I felt a delicious tremor of nerve, which was rapidly
propagated over the whole nervous system. As the action of inhaling
proceeds, an irresistible _appetite_ to repeat it is excited. There is
now a general swell of sensations, vivid, strong, and inconceivably
pleasurable. They still become more vigorous and glowing till they are
communicated to the brain, when an ardent flush overspreads the face.
At this moment the tube inserted in the air-bag was taken from my
mouth, or I must have fainted in extacy.
The operation being over, the strength and turbulence of my sensations
subsided. To this succeeded a state of feeling uncommonly serene and
tranquil. Every nerve being gently agitated with a lively enjoyment.
It was natural to expect that the effect of this experiment, would
eventually prove debilitating. So far from this I continued in a state
of high excitement the remainder of the day after two o’clock, the
time of the experiment, and experienced a flow of spirits not merely
chearful, but unusually joyous.