Whatever elements nature does not introduce into vegetables, the natural food of all animal life,—­directly of herbivorous, indirectly of carnivorous animals,—­are to be regarded with suspicion.  Arsenic-eating may seem to improve the condition of horses for a time,—­and even of human beings, if Tschudi’s stories can be trusted,—­but it soon appears that its alien qualities are at war with the animal organization.  So of copper, antimony, and other non-alimentary simple substances; everyone of them is an intruder in the living system, as much as a constable would be, quartered in our household.  This does not mean that they may not, any of them, be called in for a special need, as we send for the constable when we have good reason to think we have a thief under our roof; but a man’s body is his castle, as well as his house, and the presumption is that we are to keep our alimentary doors bolted against these perturbing agents.

Now the feeling is very apt to be just contrary to this.  The habit has been very general with well-taught practitioners, to have recourse to the introduction of these alien elements into the system on the occasion of any slight disturbance.  The tongue was a little coated, and mercury must be given; the skin was a little dry, and the patient must take antimony.  It was like sending for the constable and the posse comitatus when there is only a carpet to shake or a refuse-barrel to empty. [Dr. James Johnson advises persons not ailing to take five grains of blue pill with one or two of aloes twice a week for three or four months in the year, with half a pint of compound decoction of sarsaparilla every day for the same period, to preserve health and prolong life.  Pract.  Treatise on Dis. of Liver, etc. p. 272.] The constitution bears slow poisoning a great deal better than might be expected; yet the most intelligent men in the profession have gradually got out of the habit of prescribing these powerful alien substances in the old routine way.  Mr. Metcalf will tell you how much more sparingly they are given by our practitioners at the present time, than when he first inaugurated the new era of pharmacy among us.  Still, the presumption in favor of poisoning out every spontaneous reaction of outraged nature is not extinct in those who are trusted with the lives of their fellow-citizens.  “On examining the file of prescriptions at the hospital, I discovered that they were rudely written, and indicated a treatment, as they consisted chiefly of tartar emetic, ipecacuanha, and epsom salts, hardly favorable to the cure of the prevailing diarrhoea and dysenteries.”  In a report of a poisoning case now on trial, where we are told that arsenic enough was found in the stomach to produce death in twenty-four hours, the patient is said to have been treated by arsenic, phosphorus, bryonia, aconite, nux vomica, and muriatic acid,—­by a practitioner of what school it may be imagined.