diarrhoea and severe pain in the abdomen, especially over the sigmoid flexure. Her stools were watery, greenish in color, and without any fæcal odor, her tongue was furred, her pulse was weak and irregular, her temperature low.

The intestinal trouble increased for two or three weeks, and developed, in some twenty-five days, into an exceedingly severe inflammation of the stomach as well as of the intestines. This nearly caused the death of the patient, but was finally subdued by injecting fifty-percent. solutions of plumbic acetate, containing some morphine, in four- and five-ounce doses, and keeping them in the intestines, by pressure, for two hours at a time. Under this somewhat heroic treatment the inflammation was finally controlled, and after two months the patient gradually began to improve.

In this case, as will be noticed, there was no particular effect upon the kidneys, and after the first few days the lesions were confined to the digestive tract.

Tests for Iron.-It must be remembered that iron is a normal constituent of the blood and the red muscles of the body, forming an essential part of the hæmoglobin. Accordingly it is extremely difficult to distinguish, on chemical analysis, between the natural and the foreign iron.

According to Orfila-and his example has been followed by chemists since the foreign metal can be dissolved by steeping the finely cut tissues, as well as the contents of the stomach and intestines, in cold acetic acid, which, it is claimed, has little or no effect on the iron in the hæmoglobin. The iron in the filtrate can be separated by ammonic sulphide, in the form of black, ferrous sulphide, and after dissolving in hydrochloric and nitric acids, may be reprecipitated by ammonia as brown ferric hydrate. The solution may also be tested with potassic ferrocyanide, which will form a blue precipitate, or, after nearly neutralizing, by adding ammonic sulphocyanide, which will turn the solution a deep red.

It would probably be easier and more satisfactory to obtain a good test for iron in the fæces, or especially, after death, from the black deposits on the mucous membranes of the stomach and intestines, than from the tissues themselves. Any stains upon the bedclothes or garments of the patient should also be carefully examined for iron.

ALKALOIDAL AND OTHER ORGANIC POISONS.

BY

WALTER S. HAINES, A.M., M.D.

1. ALKALOIDAL POISONS.

The term alkaloid is used with somewhat varying significance by different authorities; but as commonly employed it refers to the bases or alkali-like bodies found in many plants, to which the latter as a rule owe their physiological effects. They are often spoken of as plant bases. The total number known is large, and embraces some of our most valuable remedial agents, and not a few of our most active poisons. There are many properties common to all, or to nearly all, of the different members of the class, and these may advantageously be considered together before taking up the individual substances.

Composition. All alkaloids contain carbon, hydrogen, and nitrogen, and all but a few contain oxygen also. The major portion of them, therefore, do not differ from one another in the elements of which they are composed, but only in the relative proportion of these elements. The chemical formulas of a few of the most important toxic alkaloids are as follows:

Physical and Chemical Properties.-Alkaloids containing oxygen are fixed solids, while those containing no oxygen are volatile liquids. They are generally crystalline, devoid of color, and are usually possessed of a bitter or pungent taste. The volatile alkaloids have a pronounced odor, but those that are fixed are odorless; they are generally of alkaline reaction to litmus, and combine with acids, neutralizing them and producing salts.

The free alkaloids are, as a rule, either insoluble or difficultly soluble in water, but they generally dissolve with readiness in alcohol, ether, chloroform, and benzine, and in many other organic liquids. Their salts, on the other hand, are usually readily soluble in water, especially when

slightly acidulated, and also in alcohol, but ordinarily they do not dissolve in ether, chloroform, or benzine. These differences in the solubility of the free alkaloids and their salts are taken advantage of, as we shall see later, in the extraction of alkaloids from complex organic mixtures.

Like the majority of organic substances, most of the alkaloids are unstable bodies, undergoing complete or partial decomposition under a great variety of conditions. All of them when heated considerably above the boiling-point of water, and sometimes at a much lower temperature, are prone to undergo change; as a rule, strong acids and alkalies and active oxidizing agents decompose them; and they all appear under suitable conditions to be acted on by micro-organisms, which eventually cause their complete decomposition. For these reasons it is highly necessary in extracting alkaloids not to subject the materials under examination to too high a degree of heat, nor, as a rule, to bring them in contact with strong acids, alkalies, oxidizing agents, or other powerful chemicals. Failure to observe these precautions can easily lead to negative results, even though an alkaloid be present in the suspected substance.

For the same reason, after death by poisoning by an alkaloid the latter sooner or later disappears from the body by decomposition. This is probably brought about chiefly through the agency of micro-organisms, which swarm in the decomposing body. It is very important, therefore, to examine for alkaloidal poisons as soon after death as possible; the longer the examination is put off, the smaller the chance of detecting the poison.

Most alkaloids when in solution are rendered insoluble and precipitated by a number of chemical compounds, which are known, consequently, as general precipitants or reagents for alkaloids. The most important of these are tannic acid, pieric acid (Wormley's reagent), phosphomolybdic acid (Sonnenschein's reagent), iodine dissolved in a solution of potassium iodide (Wagner's reagent), and potassio-mercuric iodide (Mayer's reagent). The last two are usually the most valuable, and both are of great service as general tests for the presence of an alkaloid. If neither of these reagents produces a precipitate in a suspected solution, we generally say with great certainty that no alkaloid is present; if, however, they do occasion a precipitate, the presence of an alkaloid may be suspected, although not positively demonstrated, as sev eral other substances are precipitated in a similar manner. These tests, therefore, have chiefly a negative value, but this is frequently of great importance. Wagner's reagent may conveniently be prepared by dissolving one part of iodine and two parts of potassium iodide in ninetyseven parts of water, and Mayer's reagent for qualitative purposes may be similarly made by dissolving one part of mercuric iodide and two parts of potassium iodide in ninety-seven parts of water. The precipitates given by Wagner's reagent are reddish or reddish brown, while those produced by Mayer's reagent are generally yellowish white.

Many of the alkaloids when subjected under appropriate conditions to certain chemical agents produce characteristic colors, and advantage is extensively taken of this fact in the recognition of a large number of the alkaloids. Such reactions are known as color tests. For example, if strychnine is treated with strong sulphuric acid, and a crystal of potas sium bichromate, or other oxidizing agent, is drawn through the mixture, a very brilliant play of colors ensues, beginning with blue and ending