BULLETIN No. 77b. 
8 
that the lime should be present in the boiling solution of White 
arsenic since it renders the latter insoluble as last as it goes 
into solution, thus reducing the volume of water and shortening 
the time for obtaining the arsemte. When the White arsemte is dis- 
solved alone, a larger volume of water and more time are required. 
When lime is added the precipitation goes on slowly, requiring 
more than twenty-four hours to reach completion. 
HI—Combining Arsenites With Fungicides. 
Copper sulphate (blue stone), iron sulphate (copperas), and iron 
chloride are generally used as fungicidal washes. lo test the 
solubility of arsenites in solutions of these, mixtures were made, as 
indicated in Table III, and the soluble arsenic determined after 
3 and 20 hours. The mixtures were applied to foliage at the end oi 
20 hours. This was done by dipping small twigs of mulberry, 
maple, ivy, snow berry, spirea, fig, chrysanthemum canna (left), and 
some others into the mixtures and allowing them to stand with the 
petioles in water for one week, when the effect _ was. noted, i he 
experiment, though rather crude and limited, points in its effect to 
the same conclusion drawn from Table I: That, soluble arsenic 
burns the foliage, and that the burning is in direct proportion to 
the amount of soluble arsenic. This table also shows the greater 
solubility of the arsenites in these solutions than in pure water, 
especially after they have stood for a time; and indicates that, 
when used together at all, the sooner the application is made after 
mixing, the better. 
