the danger of burning and aids the mixture in sticking to
the leaves well. If one is sure that he has at least as much lime, or
an excess of lime, it will not be necessary to test the mixture, but
if he is not, a simple test may be made with ferro-cyanide of
potassium, obtained at a drug store. A few drops of this mixture will
disappear if the lime is equal or in excess of the copper sulphate,
that is, it will be neutralized, but if it is not, they will remain a
bright purplish red. Bordeaux mixture is used in strengths varying
from three to five pounds each of bluestone and lime in fifty gallons
of water, but the former is usually sufficient.

LIME-SULPHUR.--The more important fungicides, the commercial lime
sulphur and the self-boiled lime-sulphur, are practically superseding
Bordeaux as a fungicide, not because they are necessarily better, but
because there is frequently much burning of the foliage and russeting
of the fruit from the use of the Bordeaux. This is unfortunate as the
latter is a rather more effective fungicide as well as more convenient
and pleasant to use. The self-boiled lime sulphur is a combination of
lime and sulphur which is boiled by the heat of the slaking lime
alone, and makes a pretty good substitute for the Bordeaux when it
injures foliage or fruit. This preparation of lime and sulphur differs
from the commercial form used as a winter wash in that it is wholly a
mechanical mixture and not partly chemical like the latter. It may
therefore be used on the foliage in summer at a greater strength,
there being only a very small percentage of sulphur in solution when
the mixture is properly made.

Equal amounts of lime and sulphur are used, these being from eight to
ten pounds each to fifty gallons of water. The mixture is best
prepared in larger quantities so as to get heat enough from the
slaking lime to produce a violent boiling for a few minutes. First,
place say forty pounds of lime in a barrel and pour on just water
enough to start it slaking nicely--about a gallon to each three or
four pounds of lime is usually sufficient. Then add the sulphur and
enough more water to slake the paste, keeping it well stirred
meanwhile. The violent boiling of the lime in slaking will cook the
mixture in from five to fifteen minutes, depending on the quality of
the lime and how fast it is slaked. Just as soon as the violent
boiling is over add enough cold water to stop all action. If this is
not done, some s