Frequent and long continued Use of Chloroform. Many patients have inhaled this agent hundreds of times, and it continued to produce insensibility as readily as at first. The dose does not require to be increased on account of its long use. I was informed of the case of a lady who was affected with a painful cancer, and was attended by the late Mr. Keate and Mr. Henry Charles Johnson. She inhaled chloroform at frequent intervals, by day and night, for a very long time, consuming three or four ounces in the twenty-four hours.

In November 1851, a surgeon in the north of England wrote to me respecting one of his patients, a lady, who had inhaled a great deal of chloroform, on account of neuralgia of the uterus. He said that, during that year, and principally within the last six months, she had inhaled at least two hundred ounces; that she often inhaled as much as three ounces in a day; and that it seemed to have produced very little effect on her general health, except that she seemed to be more susceptible of pain. He said that he had reluctantly yielded to the entreaties of his patient to administer it so often, and he wished for my opinion respecting the propriety of continuing its use, and what effect it would be likely to produce.

I advised that the chloroform should be continued as long as the severity of the pain rendered it necessary; and expressed my opinion, that it would produce as little ultimate effect as any other narcotic which might be used to relieve the pain. I saw the surgeon in September of the following year. He informed me that the chloroform was continued for some time after he had written to me; but that his patient had recovered from her complaint, and had left off the chloroform, and was in good health.

Mr. Garner, of Stoke-upon-Trent, has related the case of a lady, affected with neuralgia, who inhaled sixty-two ounces of chloroform from her handkerchief, in twelve days.[[157]]

SULPHURIC ETHER, OR ETHER.

History and Composition. “This liquid is first described by Valerius Cordus, in 1540, under the name of oleum vitrioli dulce. The term ether was applied to it a hundred and ninety years afterwards by Frobenius, who, in a paper in the Philosophical Transactions, described its singular properties; at the end of this paper is a note by Godfrey Hankwitz, Mr. Boyle’s operator, mentioning the experiments that had been made upon it by Boyle and by Newton.”[[158]]

The present chemical name of ether, or sulphuric ether, is oxide of ethyle. It consists of four atoms carbon, five atoms hydrogen, and one atom oxygen. Its atomic number is consequently 37.

The usual way of making ether, is to distil common alcohol (the hydrated oxide of ethyle) with sulphuric acid.

Chemical and physical Properties. Ether is a clear, colourless liquid, of the specific gravity of 0·715 at 68°. It boils at 96° Fahr.; and the specific gravity of its vapour is 2·565. It is soluble, in all proportions, in alcohol, and it is soluble in nine parts, by measure, of water. Water is also soluble in nine parts, by measure, of ether, so that after ether has been agitated with water, it retains one-tenth of its volume of that fluid. Ether is very inflammable, and, as it yields its vapour very freely, great care is required in pouring it out by artificial light. Its vapour is also very explosive when mixed, in certain proportions, with atmospheric air.

The ordinary ether of the shops contains a portion of alcohol which has distilled over with it; the alcohol should be removed by agitating the ether with twice its volume of water, before it is used for inhalation. The ether which has been treated in this way is called washed ether. The water which it takes up during the washing can be removed by distilling it from lime, or dry carbonate of potassa; but this is unnecessary, as the water does not interfere with the action of the ether when inhaled; and part of the water evaporates and is inhaled with the ether, when the atmospheric air is not already saturated with moisture.