Many of the substances used in the arts are highly poisonous. Indeed, some of the most virulent poisons are employed in very common operations. Thus arsenic is vised for coloring brass; the strong acids are used in every machine shop and foundry, and even prussic acid may be occasionally produced during the employment of prussiate of potash. The extremely poisonous cyanide of potassium is used by every photographer and electroplater. Even into the household, poisons too frequently find their way. Our matches are tipped with a strong poison, and housekeepers are often too ready with poison for the destruction of vermin. Phosphorous, arsenic and corrosive sublimate, are too frequently thus used. Paris green also we have actually seen used for the destruction of cockroaches in pantries, and corrosive sublimate is in common use as a poison for bed-bugs. As a bug poison it is generally dissolved in alcohol or whiskey, and the odor and taste have sometimes proved a strong temptation to persons who did not fully realize its dangerous character. All bottles containing such mixtures should therefore be carefully labelled, "POISON," in large letters, and when emptied they should either be broken, or very carefully cleansed, since accidents have arisen from careless persons pouring drinkable liquids into bottles that have contained solutions of corrosive sublimate, which solutions, after drying up have left the bottle apparently empty, but in reality containing an amount of poison sufficient to destroy several lives.

In all cases where poisons have been swallowed, the proper course is first to neutralize the deleterious agent, and then to procure its rejection by means either of the stomach-pump or an emetic. The stomach-pump is, of course, the best and most expeditious agent. It requires but a few moments to insert it and remove the contents of the stomach; fresh supplies of water and the proper antidotes can then be poured into the organ, so that in a few minutes the last traces of the poison can be removed- But as the stomach-pump is to be found in the possession of physicians only, reliance must in general be placed upon emetics, of which the best is, unquestionably, mustard - an article which is to be found in almost every household. It is generally conceded by physicians that mustard is the mildest, most rapid, and most efficient emetic known. It is prepared for use as follows: Take about a plump dessert-spoonful of genuine flour of mustard (if it be mixed with wheat flour or turmeric, more will be needed), and mix it rapidly in a cup with water to the consistency of thin gruel, and let this be swallowed without delay or hesitation. In a very few seconds the contents of the stomach will be ejected. Before the emetic action has entirely ceased, a little lukewarm water, or still better, warm milk, should be forced down. This will be thrown off immediately, and will serve to rinse out the stomach and remove the last traces of deleterious matter.

By the time the operation of the emetic has ceased, a physician will probably be in attendance, and to his care the patient should be at once confided.