8 BULLETIN 1027. U. S. DEPARTMENT OE AGRICULTURE. 
In 1893 Davis (30) reported the determinations of arsenic on 
celery that had been sprayed with Paris green at the rate of 1 pound 
to 175 gallons of water. The results, obtained on the celery washed 
without separating the stalks and prepared as for market, were as 
follows: Sprayed once, 0.0244 grain of arsenious oxid per pound of 
celery; sprayed twice, 0.0368 grain of arsenious oxid per pound of 
celery. 
In 1S93 Beach reported (12) the presence of from 0.00012 to 0.001 
per cent of copper in celery that had been sprayed with Bordeaux 
or ammoniacal copper carbonate solution, and 0.00081 per cent in 
unsprayed celery, concluding that "these investigations show that 
when this sprayed celery was stripped and ready for market the 
sprayed plants were no more poisonous than the unsprayed.'' 
In 1894 Kinney (68) stated that the skins and stems of pears 
which had been sprayed five times with Bordeaux mixture (6 pounds 
of copper sulphate, 4 pounds of lime, and 22 gallons of water), and 
upon which the spray was still visible at harvest contained only 
0.016 grain of copper oxid per pear, for which reason no serious 
objection to this treatment could be raised from a hygienic stand- 
point. 
In 1S94 Garman reported (49) that the skins and ends of six apples 
from a tree that had been sprayed once with London purple and five 
times with Paris green at the rate of 1 pound to 160 gallons of water 
showed on analysis no arsenic and only an unweighable amount of 
copper. The flesh and cores of these apples gave no reaction for 
arsenic or copper. He reported also (50) that cured tobacco which 
had been sprayed with arsenites. at the rate of 1 pound to 160 gallons 
of water, gave on analysis 0.077 grain of arsenious oxid and 0.042 
grain of copper oxid per pound with one spraying with Paris green: 
0.133, 0.259, and 0.329 grain of arsenious oxid and 0.126, 0.210. and 
0.322 grain of copper oxid per pound with two sprayings with Paris 
green: and 0.245 grain of arsenious oxid per pound with two spray- 
ings with London purple. Later (1904) this author stated (51) that 
arsenites such as Paris green can be used on cabbage without leaving 
a trace sufficient for recognition by the chemist. In 1901, cabbages 
which had been sprayed with Paris green or lead arsenate showed on 
analysis " traces of poison present.'' In 1902, and again in 1903, 
sprayed cabbages were analyzed, but the chemist "was unable to find 
a trace of poison present." 
In 1897 Teyxeira (123) found from 20 to 50 milligrams of copper 
in 1 kilogram of juice from tomatoes that had been sprayed with 
copper sulphate, and none after treatment with Bordeaux, unless 
the skin was cracked. He stated that the copper sulphate penetrates 
the skin into the flesh, but that the copper-lime mixture does not. 
