PARTS TO WHICH MEDICINES ARE APPLIED.

55

are administered by the stomach, their properties are more or less alteredby the digestive powers of this viscus; and that by injecting medicines atonce into the veins, we avoid this intluence. This statement, however, isnot accurate, since Drs. Christison and Coindet have shown that somesubstances are decomposed even in the blood, or at least that they cannot berecognized in this fluid. Furthermore, it has been proved that the effectsare of the same general nature as when medicines are applied to the skinor stomach ; thus, tartar emetic vomits, senna purges, opium stupifies, andso on. So that some of the supposed advantages of this operation have noreal existence, while several objections to it exist: such as the danger ofintroducing air into the veins, or of throwing in too large a dose of the re-medy (for a slight excess in some cases may prove fatal), or of the occur-rence of phlebitis. These, then, are sufficient reasons for not resorting tothis practice, except on very urgent occasions; for example, to excitespeedy vomiting when the patient is unable to swallow. Kohler (men-tioned by Dieff'enbach, who notices also several other analogous cases)preserved the life of a soldier, in whose throat a piece of beef tendon wassticking, by throwing a solution of six grains of tartar emetic into a veinof the arm : vomiting was induced, and the meat expelled. Meckel in-jected two grains of this salt, dissolved in water, into the veins of awoman, to restore suspended animation, from immersion in water.

In some obstinate and dangerous diseases this operation is admissibleas a last resource; for example, in cases of poisoning, in hydrophobia, inmalignant cholera, &c. As plethora appears to diminish absorption, ithas been proposed to throw tepid water into the venous system in casesof narcotic poisoning, and thus to cause artificial plethora, in order toprevent the occurrence of the symptoms of poisoning by stopping absorp-tion. Vemiere found three grains of nux vomica produced no effectwhen applied to a wound in a dog into whose veins water had beenthrown; and he asserts, that by the early use of aqueous injections wemay prevent the developement of contagious diseases. Magendie hastried the effects of injecting tepid water into the veins in hydrophobia.The operation was first performed at the Hotel-Dieu, at Paris , in Octo -ber, 18-23: the convulsions were stopped, but the patient died in a day ortwo afterwards. This operation has been several times repeated, andwith the same results. In June 1832, I tried it on a patient (afflictedwith this terrible disease) under the care of the late Mr. Bennett, of theCommercial lload: the patient was a boy about nine years of age ; he wasnearly insensible at the time I performed the operation. I threw in aboutone quart of tepid water without any obvious effect on the pulse: noconvulsions were subsequently observed, but the patient died in a fewlioms. Saline solutions were injected into the veins in malignant cholera,and often with apparent advantage. Purgatives, narcotics, &c. have beenthrown into the veins by different physiologists, and in most cases theeffects observed were similar to, though more powerful than, those pro-duced when these agents were administered by the stomach. To thisstatement, however, the oils are an exception ; for when injected into theveins in large quantities they interrupt the circulation, and produce akind of asphyxia.

Agency of Galvanism. —It has been proposed to assist the introduc-tion of certain medicinal particles into the blood by galvanism. Thispractice was first adopted with iodine in 1823, by Dr. Coster, (Archives