In 1769 Alphonse Leroy, of Paris, reported a curious experience. He was sent for to a patient apparently on the point of death from phthisis. Seeing that the case was hopeless, he prepared and administered a placebo of sugared water. Calling the next day, Leroy found his patient somewhat revived, and on examining the sugar which he had used for his solution, he found that some phosphorus had been kept in it for a long time. The patient was much too far gone to recover, but she survived for fifteen days, and Leroy attributed this amelioration to the phosphorised water which he had accidentally given her. Gahn discovered phosphorus in the bones in 1768, and in 1779 another German chemist named Hensing ascertained its presence in a fatty matter which he extracted from the brain. Medical theories were naturally based on these observations. Couerbe, a French chemist quoted by Dr. Churchill, wrote thus in 1830: “The want of phosphorus in the brain would reduce man to the sad condition of the brute; an excess of this element irritates the nervous system, excites the individual, and throws him into that terrible state of disturbance called madness, or mental alienation; a moderate proportion gives rise to the sublimest ideas, and produces that admirable harmony which spiritualists call the soul.” British practitioners took but very little notice of phosphorus as a remedy in the first century of its career, although it remained for a large part of that period an English product. It is rather curious, too, that neither in this country nor on the Continent did it get into the hands of the empirics, as mercury, antimony, and other dangerous drugs did. It may be supposed that it was not so much the danger that checked them as the pharmaceutical difficulties in the way of preparing suitable medicines. The earliest preparations of phosphorus, such as Kunckel’s pills, were a combination of it in a free state with conserve of roses. This method was gradually abandoned on account of the difficulty of subdividing the phosphorus so perfectly that the dose could be measured accurately. But as Dr. Ashburton Thompson remarks,[3] “although it is not so specifically mentioned, the uncertainty of action which imperfectly divided phosphorus exhibits” had something to do with the rejection of the old formulas. That is putting it very gently. The three-grain doses must have killed more people than they cured. The author just quoted says that in the early days “the dose employed seldom fell below 3 grains, while it occasionally rose as high as 12 grains.” Even Leroy, he adds, instituted his experiments by taking a bolus of 3 grains, and he did not seriously suffer from it. The recommended dose has been regularly declining. In 1855 Dr. Hughes Bennett gave it at one-fortieth to one-eighth of a grain. The Pharmacopœia now prescribes one-hundredth to one-twentieth of a grain. THE HYPOPHOSPHITES.