While the "laughing gas" method of obstetric anesthesia did not gain notoriety and publicity from being exploited in magazines and other lay publications, it did get its initial boost in a very unique and unusual manner. A gentleman who manufactured and sold a "laughing gas" and oxygen mixing machine for the use of dentists, insisted that this method of anesthesia should be used in the case of his daughter, who was about to be confined. This patient was kept under this nitrous oxid anesthetic for six hours--came out fine--no accidents or other undesirable complications affecting either mother or child, and thus another and safe method of reducing the sufferings of childbirth has been fully demonstrated and confirmed, although it had previously been known and used in labor cases to some extent. Starting from this particular case in 1913, many obstetricians began experimental work with "gas" in labor cases; and, at the time of this writing, it has come to occupy a permanent place in the management of labor, alongside of chloroform, ether, and "twilight sleep." ANALGESIA VS. ANESTHESIA The reader should understand the difference between analgesia and anesthesia. Anesthesia refers to the condition in which the patient is more or less unconscious--wholly or partially oblivious to what is going on, and, of course, entirely insensible to all pain. Analgesia is a term applied to the loss of pain sensation. The patient may not be wholly or even partially unconscious--merely under the influence of some agent which dulls, deadens, or otherwise destroys the realization of pain. This is the condition aimed at by the proper administration of any form of "twilight sleep," whether by the scopolamin-morphin method, or by the nitrous oxid ("sunrise slumber") method. Any method of treatment which can more or less destroy the pain of labor without in any way interfering with its progress, and which in no way complicates its course or leaves behind any bad effects on either mother or child, must certainly be hailed with joy by both the patient and the physician. While chloroform has served these purposes fairly well, there have been numerous drawbacks and certain dangers; and it was the knowledge of these limitations in the use of both chloroform and ether, that has led to further experimentation and the development of these newer methods of producing satisfactory analgesia--freedom from pain--without bringing about such a state of profound anesthesia as accompanies the administration of the older methods. It should be borne in mind that in using "sunrise slumber" (nitrous oxid) for labor pains, the gas is so administered that the patient is just kept on the "borderline"--in a typical "twilight" state--and not in the condition of deep anesthesia which is developed when nitrous oxid is employed by physicians and dentists as an anesthetic for major and minor surgical operations.