dental poisoning from it. An adult, unable to sleep, took from a closet a bottle containing a colorless fluid, which he supposed to be a solution of potassium bromid; the room being dimly lighted, he did not read the label, but took a tablespoonful of what proved to be ammonia-water. He detected the poison as soon as it was tasted or smelt and before it was swallowed. For about a week his mouth and tongue were raw, swollen, and painful; he was unable to masticate or swallow solid food.

The liquefied ammonia gas (NH) is used in ice-factories and refrigerators. Sometimes the receivers burst and the vapors fill the room, with deadly consequences to those who are exposed to them. Sometimes, to arouse fainting persons, it is given too strong by inhalation. In the five years from 1883 to 1887 inclusive, 45 fatal cases were registered in England and Wales. Of 50 cases caused by aqua ammoniæ, Witthaus found that 29 were accidental, 18 suicidal, and 3 homicidal. Of 47 cases, 27 died and 20 recovered.

2

Properties.—Ammonia gas (NH) is a colorless gas having a pungent odor, irritating to the eyes and the mucous lining of the air-passages, turning moist red litmus-paper blue. Under a pressure of 63 atmospheres it is condensed to the liquid used in ice-machines to create a freezing temperature by its evaporation. Ammonium hydroxid is a strong solution of the gas in water. Water will absorb 700 times its volume at ordinary temperatures and thereby acquire the alkalinity, the pungency, and the chemical properties of the gas itself.

Pharmaceutic Preparations.-Aqua ammoniae fortior contains 28 per cent. by weight of ammonia gas, has a specific gravity of 0.900, and is a powerful corrosive. Aqua ammonice has 13 times more water, only 10 per cent. of ammonia gas, and a specific gravity of 0.960. Spiritus ammonia is a solution of the gas in alcohol, of the same strength as the aqua, and better adapted for internal use. When it has added to it the carbonate, with small quantities of oils of nutmeg, lemon, and lavender, the aromatic spirits is produced. Ammonii carbonas occurs as whitish angular masses, giving off the characteristic irritating and alkaline vapor of ammonia, and caustic in strong solution.

Symptoms. The nature and gravity of the effects will depend greatly on the strength of the solution, and on whether or not the subject received a strong dose of the vapor by the lungs. The direct chemical action upon vital tissue is the same as that of potassium hydroxid, though less in degree—i. e., the albumin is dissolved, the fatty matter saponified, and the water abstracted. The respiratory symptoms are a suffocative feeling due to spasm of the glottis, followed by a sense of pain and weight in the chest, with an irritative cough due to inflammation of the larynx and trachea.

The symptom due to the local caustic effect of the fluid is burning pain in mouth and throat, extending to the stomach if the poison went so far. There are salivation, vomiting, and difficulty in swallowing. As

1 Fairbrother, St. Louis Medical and Surgical Journal, 1887.

2 Witthaus and Becker, Medical Jurisprudence, Forensic Medicine, and Toxicology, New York, 1896.

a result of a free absorption of the poison by the lungs and stomach cases display grave remote effects sometimes with great rapidity. The heart's action is sometimes arrested in a few minutes; sometimes there is immediate unconsciousness with coma, and death in a few minutes; sometimes there is unconscious delirium, soon ending in death.

A typical case is that reported by J. M. DaCosta :1 A man aged fortysix years, took by mistake a large quantity of strong aqua ammoniæ, but swallowed only a small portion. In a short while the breathing was frequent and stertorous, the voice husky, the glottis, uvula, tonsils, lips, gums, and tongue all swollen. There were headache and delirium, enlarged cervical lymphatics, cough with bloody expectoration. The urinary symptoms were remarkable, the secretion being diminished, but dense, alkaline, highly albuminous, showing separate blood-cells and many tube-casts, epithelial, hyaline, and granular. The serious symptoms soon subsided and convalescence set in after four days.

Fatal Dose.-A teaspoonful of the stronger aqua ammoniæ has in at least one instance proved fatal, and two fluidrams have caused death in two or three other cases. Recovery, however, has sometimes followed much larger doses, such as a tablespoonful, and even upward of a fluidounce has been taken without fatal results.

Fatal Period. By suffocation and syncope death has occurred in four minutes after inhalation of the gas. On the other hand, death may occur after many months as the result of the starvation due to stricture of the gullet or pylorus.

Treatment. The antidotes are very weak vinegar, lemon-juice, oil, butter, and milk. The sequels are to be treated as they arise.

Postmortem Appearances. These are not markedly different from the inflamed state of the alimentary tract as caused by the other caustic alkalis. When the vapor acts as an irritant upon the air-passages, an inflamed state of the larynx and even of the bronchi may be found.

Tests. Ammonia gas turns red litmus-paper blue, and makes a white smoke when mixed with the fumes of a rod wet with hydrochloric acid. All the salts are volatile when heated, and evolve the gas spontaneously or when heated with calcium hydroxid. Platinum chlorid yields a yellow precipitate like that given by potassium.

Detection.-Owing to the volatility of ammonia, its hydroxid and its carbonate, these soon escape from the body. During life, or soon after death, detection is easy by the characteristic odor. If the volatile preparation has been fixed by the antidote, the vapor can be developed by heating the material with lime. This vapor will be alkaline and form white fumes with hydrochloric acid.

If the organic material to be examined is putrid, allowance must be made for the ammonia produced by putrefaction. This is never enough to develop the dense white fumes of ammonium chlorid from a rod wet with hydrochloric acid. The amount may be estimated by distillation, neutralizing the distillate with hydrochloric acid, evaporating nearly to dryness, and precipitating the double chlorid of ammonium 1 Boston Medical and Surgical Journal, 1891. 2 Guy's Hospital Reports, 1871.

and platinum by adding excess of alcoholic solution of platinum chlorid. After filtration, the precipitate is washed with alcohol, dried, and weighed; 100 parts represent 8.6 parts of ammonia (NH3).

IRRITANT POISONS.

In the class of irritants are placed a large number of poisons that figure prominently in the bills of mortality. Some of them are of animal and some of vegetable origin, but the present study is limited to those derived from the mineral kingdom. They cause pain in the throat, gullet, and stomach, great thirst, nausea and vomiting, abdominal tenderness, purging and straining, with bloody stools, scanty, and often albuminous, urine. After death the alimentary tract shows an inflamed condition not very characteristic except when it involves the entire length from mouth to rectum, an extent never found in the specific inflammatory affections of the stomach and bowels, such as cholera morbus and acute gastric or intestinal catarrh. There are redness and swelling of the mucous glands, dark patches of infiltrated blood, softening, and, as a secondary result of the inflammation, ulceration and perforation (see Plate 5). With those minerals that add remote effects to the local ones just given there are symptoms and pathologic changes referable to the specific organs affected, as the heart, liver, and kidney.

PHOSPHORUS.

(Chemical symbol, P.)

This element is a constituent of the tissues and fluids of the human body, occurring largely in the bones as calcium phosphate and in the nervous centers as a compound with fat and albumin. Ever since it was first used to tip lucifer matches its poisonous properties have been known; indeed, on the Continent of Europe it has been the favorite rat poison. While the other active poisons are guarded by law from general distribution, this one is easily obtained as the heads of matches and as " rat-paste,' which contains from 1 to 4 per cent. of phosphorus mixed with oil, flour, sugar, and coloring-matter.' It is rarely used by homicides, but frequently by suicides, and sometimes children ignorantly eat the paste or suck the heads of matches. In the five years from 1883 to 1887 inclusive there were registered in England 71 deaths from poisoning by phosphorus and matches. More than half the cases were in children. Of the adults, nearly all were suicidal, a few only being accidental and none criminal. In spite of the garlicky taste and smell, it could be given in coffee, the more easily if at the same meal onions or garlic had been Out of 522 cases studied by Witthaus,3 in only 10 was the

eaten.

1 Coster's Rat and Roach Erterminator contains 2.13 per cent. of phosphorus, and though the buyer is assured by the label that it is "not poisonous," two fatal cases have been reported from taking it. Parson and Co.'s Vermin Exterminator has 0.4 per cent. of free phosphorus.

Repts. of Registrar-general.

3 Witthaus and Becker, Medical Jurisprudence, Forsenic Medicine, and Toxicology, New York, 1896.