This section is from the book "The Gardener's Monthly And Horticulturist V21", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
Our venerable friend and florist Mr. P. Hen-deson, puts things very nicely in his argument that plants do not feed through the pores of the leaves. Still, Mr. Editor I have to take sides with you and state that so far as my experience goes, plants can be made to grow better, produce larger and more abundant flower trusses and also thriftier looking by stimulating them through the pores of the leaves. I submit a formula for all the readers of the Monthly to experiment with, viz: Multiply the length by the breadth of your house and find number of square feet. To every 200 square feet, take one teaspoonful of spirits of ammonia, and two tea-spoonful of water. Heat a pan or shovel very hot and walk through the house pouring the mixture on the hot surface so as to vaporise it.
This to be done once a week, preferably in the evening. And if after two months trial of this method no benefit is derived, I will then give in that I am wrong. No harm can be done in any case, whether foliage plants, orchids or ferns, the result with me has always been the same. I hope all will try it, including Mr. Henderson, and report on its merits or demerits.