This section is from the book "Commercial Gardening Vol1", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
This may be had in a powdered or paste (Blundell's) form, the latter being the better. One ounce to 10 to 25 gal. water is used as an insecticide to prevent attacks of Codlin Moth, in spring, and other pests. If used too strong it will burn the leaves. This may be guarded against, however, by adding to the liquid an equal or double weight of lime in proportion to the quantity of Paris Green used. By adding a quantity of whitening to the solution it will be easy to see where the spray is distributed.