After death, marks of inflammation are found in the alimentary canal, kidneys and bladder, and the genital organs. _Tests._—The detection of Spanish flies, if taken solid, depends mainly on the presence of the shining particles already alluded to, in the stomach, or in the vomited matters. To make their nature certain, however, an extract of the suspected materials should be prepared and treated repeatedly with chloroform or ether. This fluid is to be allowed to evaporate till only a few drops are left, which may be applied on lint to some portion of the body where the skin is fine, as the fore arm, the part being covered by a bit of isinglass plaster, or goldbeaters’ skin. The vesication produced is the test of the presence of cantharides. No antidote is known. Vomiting must be excited or encouraged; and linseed tea, and gum water, or gruel copiously administered. The warm bath will afford great relief. Oil must be avoided, on account of its being a solvent of the active principle (cantharidine) of this poison. IV.—NEUROTIC POISONS. CHAPTER XXII. NARCOTICS. NEUROTICS, ACTING ON THE BRAIN AND PRODUCING SLEEP. OPIUM. OPIUM is the inspissated juice of the unripe capsules of the _Papaver somniferum_, or white poppy, and is a very complex substance. Its principal properties, however, are due to the presence of _morphia_, as meconate of morphia; but others of its constituent substances undoubtedly modify its action. It is sometimes used as a poison in its crude state, but more frequently in solution in alcohol, forming tincture of opium, or laudanum. Unfortunately, opium is the powerful ingredient of most soothing syrups for children, to whom opium is at all times especially dangerous; and many who do not die from its direct effects, do from the wasting indirectly produced. Of domestic quieting physic the chief preparations are Godfrey’s Cordial, supposed to consist of one grain of opium in two ounces; and Dalby’s Carminative, which is one-fourth weaker.