what renders it valuable, for the fever tick
is hard to kill. But, like a keen-edged tool, it may be decidedly dangerous
if ignorantly or carelessly handled. Three possibilities of danger must be
kept constantly in mind; danger to oneself, danger to other persons, danger
to animals.

The dry, powdered white arsenic should be kept in a tightly covered pail,
plainly labeled. Paper bags are unsafe because they easily burst, and
arsenic so scattered about looks harmless enough. In weighing or otherwise
handling the arsenic avoid raising dust or breathing it in, if raised, and
keep it off the skin and clothing. In mixing or boiling stock solutions
work only in a well-ventilated place, and on the windward side of the
kettle so that steam arising from it will not be inhaled.

The stock solutions are in some respects more dangerous than the original
substance because the arsenic in them is already in solution and can act
very quickly. If any gets on the skin or clothing it must be washed off
without delay. Cattle must be kept away from such solutions or from
anything that has been in contact with them, for cattle craving salt have
been poisoned by licking the outside of leaky barrels and by licking the
earth around dipping vats where a little concentrate had been carelessly
spilled in charging the vat. All such poisoned earth must be removed,
buried, and replaced by fresh.

The diluted bath is naturally much less dangerous, but no chances can be
taken with it. No puddles from which animals may drink should be allowed to
accumulate. The persons who do the dipping should not allow the skin or
clothing to be wet by the dip any more or any longer than absolutely
necessary. When spraying, the operator should see to it that neither he nor
the animals inhale any of the spray.

When a vat is to be emptied the approved practice is to run the waste bath
into a pit properly guarded by a fence, where it will gradually seep away
under the surface and do no harm, provided only that seepage can not be
carried to a well, stream, or spring from which any person or domestic
animal may drink.

The symptoms of arsenical poisoning are rather variable and also depend on
the size of the dose and the method of administration. If an animal sickens
or dies shortly after dipping it by no means follows that arsenical
poisoning or any other effect of the dipping is the cause. Very few cattle
relative to the total number dipped have suffered undoubted