412 STATE HORTICULTURAL SOCIETY. 



Agricultural college, confirmed these conclusions. It is safe, then, to 

 assume that the only way in which fruit or vegetables can convey the 

 poison to the consumer will be through the very minute quantity of arsenic 

 left upon the edible part of the plant. Against the possibility of such an 

 effect the following facts may be urged: 



(1) It would seem at first glance that the use of an arsenical poison 

 upon a plant like the cabbage would be very unsafe to recommend, yet 

 Paris green and London purple are used upon this crop to kill the several 

 species of leaf -eating worms which are so destructive to it, and an absolute 

 absence of all danger where the application has been properly made has 

 been recently shown by Prof. Gillette of the Agricultural experiment 

 station of Colorado, by the following reductio ad absurdum : 



* * * Where the green is dusted from a bag in the proportion of 1 ounce of the 

 poison to 100 ounces of flour and just enough applied to each head to make a slight 

 show of dust on the leaves, say for twenty- eight heads of cabbage, 1 ounce of mixture, 

 the worms will all be killed in the course of two or three days, while the average amount 

 of poison on each head will be about one seventh of a grain. Fully one half of the 

 powder will fall on the outside leaves and on the ground, and thus an individual will 

 have to eat about twenty-eight heads of cabbage in order to consume a poisonous dose 

 of arsenic, even if the balance of the poison remained after cooking. 



(2) In case of spraying apple orchards for the codlin moth there is 

 scarcely a possibility of injury to the consumer of the fruit. A mathe- 

 matical computation will quickly show that where the poison is used in 

 the proportion of 1 pound to 200 gallons of water (the customary pro- 

 portion) the arsenic will be so distributed through the water that it will be 

 impossible for a sufficient quantity to collect upon any given apple to have 

 the slightest injurious effect upon the consumer. In fact, such a compu- 

 tation will indicate beyond all peradventure that it will be necessary for 

 an individual to consume several barrels of apples at a single meal in order 

 to absorb a fatal dose even should this enormous meal be eaten soon after 

 the spraying and should the consumer eat the entire fruit. 



(3) As a matter of fact, careful microscopic examinations have been 

 made of the fruit and foliage of sprayed trees at various intervals after 

 spraying, which indicate that after the water has evaporated the poison 

 soon entirely disappears either through being blown off by the wind or 

 washed off by rains, so that after fifteen days hardly the minutest trace 

 can be discovered. 



(4) In the line of actual experiment, as indicating the very finely divided 

 state of the poison and the extremely small quantity which is used to each 

 tree, Prof. A. J. Cook of the Michigan Agricultural college, has con- 

 ducted some striking experiments. A thick paper was placed under an 

 apple tree which was thoroughly sprayed on a windy day so that the drip- 

 ping was rather excessive. After the dripping had ceased, the paper 

 (covering a space of 72 square feet) was analyzed, and four tenths of a 

 grain of arsenic was found. Another tree was thoroughly sprayed and 

 subsequently the grass and clover beneath it was carefully cut and fed to 

 a horse without the slightest sign of injury. 



The whole matter was well summed up by Professor Riley in a recent 

 lecture before the Lowell Institute, in Boston, in the following words: 



The latest sensational report of this kind was the rumor, emanating from London, 

 within the last week, that American apples were being rejected for fear that their use 

 was unsafe. If we consider for a moment how minute is the quantity of arsenic that 

 can, under the most favorable circumstances, remain in the calyx of an apple, we shall 



