142 HORTICULTUEAL MANUAL. 



grapes. The writer in 1882 was surprised to see vines 

 with leaves and fruit covered with a light-blue coloring 

 matter. It was soon found that the vines thus " poisoned " 

 as the people were led to believe were the only ones 

 that retained their foliage in the infected districts in 1882. 



It was not until 1885 that Millardet gave the formula 

 for making what is now known as Bordeaux mixture, but 

 it was at first applied with a broom. So far as known to 

 the writer the first perfected spraying machines used in 

 Europe were made in the United States. 



In the United States the first spraying, or rather 

 sprinkling done with a broom, was in 1860, when the 

 currant and gooseberry worm made its first appearance. 

 A solution of hellebore in water was then used. In 1877 

 the Colorado potato-beetle had extended over Iowa, and 

 the first remedy used was spraying with Paris green, which 

 was only partially successful on account of its varied 

 purity. The sudden demand for the article led to 

 adulteration to a remarkable extent. In 1877 an agent of 

 Hemanway & Co., of London, visited Ames, Iowa, with a 

 view to securing a trial at the Agricultural College of a 

 waste product of their analine dye-works as an insecticide. 

 In February, ]878, three kegs of the waste under the 

 name of " London purple" reached Ames and were tested 

 in the summer of 1878 by the writer. At Ames the 

 potato-beetle was then at its height of development and 

 destruction. In the fall of 1878 the writer gave in the 

 Iowa Agricultural College Quarterly the following state- 

 ment: "Last winter the college received for trial a 

 quantity of a material called by the manufacturers London 

 purple, and designed to be used for the Colorado potato- 

 beetle (the potato-bug of common parlance). L'pon trial 

 it was found very valuable, killing the old as well as the 

 young insects with great certainty. The virtue of London 



