ve agents that can be used in
the disinfection of barns, milkrooms, etc. Besides being a fairly
strong disinfectant, it has a tendency to absorb odor, it encrusts
the walls and lightens the interior of rooms. It can be applied with
a brush or with a spray pump.

=Carbolic acid and cresol compounds.= These substances are among the
cheapest and best disinfectants, but their use in the dairy is not
advisable, on account of the penetrating and lasting odor. They can
be used to advantage on the farm. Some of the proprietary compounds,
as Zenoleum, Kresol, etc., are easily applied, since they mix
readily with water in all proportions, forming a milky-white
emulsion that can be easily applied. They are less caustic and less
poisonous than carbolic acid.

=Corrosive sublimate.= Corrosive sublimate is the most efficient
disinfectant under ordinary conditions. It is such an intense poison
that it must be used with caution in places to which stock have
access, or in the dairy. A solution of one part of the salt to a
thousand parts of water (half ounce to 4 gallons of water) is the
standard generally used.

For gutters, drains, and waste pipes in factories, ferrous sulphate
(green vitriol), and copper sulphate (blue vitriol), can be used to
advantage. They are to be classed as deodorants rather than as true
disinfectants. Since they have no odor of their own, they can be
used in any amount in the dairy.

=Sulphur= can be used to advantage in the destruction of mold spores
in cheese rooms, but the effect of the vapors of burning sulphur on
germ life is relatively slight, unless there is an abundant supply
of moisture in the air of the enclosed space, in which case
sulphurous acid is formed which has a much greater effect. To have
the desired effect sulphur should be burned at the rate of three
pounds to each one thousand cubic feet of space, and the room kept
sealed for at least twelve hours. If the sulphur is placed in an
iron kettle which is set in a vessel of water, danger from fire
will be avoided, and the heat generated by the burning sulphur will
evaporate sufficient water to increase the effect of the fumes.

=Formalin.= Another disinfectant that may be used as a liquid or as a
gas is formalin, which is a watery solution of the gas,
formaldehyde. It is much more powerful in its action than sulphur,
and has a great advantage over corrosive sublimate and other strong
disinfectants in that it is not so poisonous to animal