Voi.. LXVIII, No. 3095. NEW YORK, MAY 22, 1909. weekly, $i.oo per year. 
BORDEAUX MIXTURE FOR POTATOES. 
HOW MADE AND HOW APPLIED. 
The Whole Story Told. 
PREPARING THE MIXTURE.—Weigh into a 
bag 50 pounds of copper crystals (blue vitriol). Ac¬ 
curately measure 48 gallons of water into a bar¬ 
rel, and at the water line cut a notch, which is 
a gauge for the future fillings. Suspend bag of 
copper so that three-quarters of it will be im¬ 
mersed, and during a night the copper will practi¬ 
cally all dissolve and make an even 50 gallons of 
copper water or stock solution. Copper charged 
water is heavier, therefore goes to bottom of barrel, 
THE POTATO 
which explains why copper should be suspended. 
Before using thoroughly stir up stock solution and 
dip out one gallon for one pound of copper. S&venty- 
five, yes, 100 pounds of copper can be likewise dis¬ 
solved and used accordingly, but more time is re¬ 
quired. Water will take up about three pounds of 
copper per gallon, which is a saturated solution. 
Copper water destroys galvanized or iron pails. Fresh 
burned Ohio Marblehead stone lime in barrels is 
prepared. This is carefully slaked, which requires 
skill in order to have a superior quality of milk 
of lime. A stock solution of lime water is kept in 
readiness. Tw« little trenches about eight inches 
deep, rounded bottoms, are dug in the ground for 
sprayer wheels to back into at filling place. This 
keeps horse and sprayer at proper place, also lowers 
sprayer tank, which helps in filling, especially if water 
is dipped. • 
FILLING THE SPRAYER—Sprayer is fitted 
with funnel and a four-quart milk can with whole 
bottom cut out and fine brass milk strainer cloth 
soldered on. This strainer rests in funnel .and 
can be instantly taken out for cleaning. What¬ 
ever goes into the tank is thoroughly strained, 
thus avoiding a large part of the usual annoyance 
at the nozzles. First, three pails of clear water is 
put into tank, next four pails of lime water and 
strainer washed with four more pails of clear water 
and strainer cleaned. Water and lime water are put 
into tank first, because pump and pipes fill by gravity, 
and will not rust as the copper water would. How¬ 
ever, invariably the usual instructions say put copper 
water in first. Next the five gallons of copper water, 
depending on size of tank, is added, strainer washed 
water added, which has settled just about right upon 
returning to refill. Paris green is used exclusively 
for an insecticide, at the rate of pound per acre, 
and will completely appease the insatiable appetite of 
the Colorado Potato beetles, and cause terrible execu¬ 
tion among them, especially the newly hatched, if 
green is pure, evenly distributed and weather favor¬ 
able. We have applied many hundred pounds of 
green for ourselves and the public, and found it no 
picnic. Green is mixed with water in a pail, and 
added to Bordeaux last, only when bugs are preva¬ 
lent. The 5-5-50 formula is followed. The particular 
formula is not so important as applying either a weak¬ 
er or stronger Bordeaux, vigorously, liberally and 
DIGGING ARMY ON A NEW YORK POTATO FARM. Fig. 224. 
and Bordeaux tested and if right tank is filled with 
water. Previously at a drug store, 10 cents’ worth 
(an ounce) of ; ferrocyanide of potassium is purchas¬ 
ed. This is put into a pint bottle and filled with 
water, and shaken "up * occasionally. A part of this 
test is put in a clean oil can and kept, within arm’s 
length, at filling place.’ A drop or so of this test put 
into Bordeaux indicates whether or not the Bor¬ 
deaux is properly put together. Tf test shows any 
discoloration in Bordeaux, lime water should be add¬ 
ed until test shows 'clear, and no change in color. 
Lime in excess is always safe. The copper in solu¬ 
tion is the agent which destroys the blight spores. Lime 
probably helps some and prevents the caustic action 
of the copper. Tf copper is in excess there is grave 
danger of burning the potato foliage. This ferrocv- 
anide of potassium test is simple, cheap and a safe 
guide, the same as a compass is to the sailor, watch 
to the engineer, or rule to the carpenter. Before 
going to field, fresh lime putty is stirred up and 
on time. All chemicals are early purchased and on 
a guaranteed analysis. 
THE SPRAYER.—The sprayer is a one-horse, 
two-wheeled (four-foot wheels), homemade affair, 
and has a 3x5-inch double-acting Rumsey force 
pump, large air chamber, relief valve, pressure 
gauge, revolving agitator, stop cocks, which shut 
off and hold pressure, or cocks can be instantly 
changed so pump returns solution to tank from 
bottom, which is always done while on way to 
field. This is a very important—yes, vital considera¬ 
tion, because it so thoroughly mixes Bordeaux, green 
or both, that every drop of solution from first to 
last is of same quality. Every sprayer should be 
thus arranged. Pump is geared one to one and one- 
fourth times, develops and maintains a 75-pound 
pressure, which can, at will, be varied and regu¬ 
lated by relief valve. Valves, relief valves and all 
vital parts of a sprayer should be easily accessible 
for cleaning or adjustment. Sprayer has six Dem- 
