Page:An introduction to physiological and systematical botany (1st edition).djvu/234

 204 ideas, of the deleterious effects of this air on animal life, too far; for no mischief has ever happened, as far as common experience goes, to persons sleeping in apple or olive chambers, neither do the inhabitants of the confined huts in Covent-garden market apparently suffer, from living day and night among heaps of drying herbs. Mischiefs have unquestionably arisen from flowers in a bed-room, or any other confined apartment, but that is to be attributed to their perfumed effluvia. So the bad effects, observed by Jacquin, of Lobelia longiflora on the air of a hot-house, the danger incurred by those who sleep under the Manchineel-tree, Hippomane Mancinella, or, as it is commonly believed, under a Walnut-tree, are probably to be attributed as much to poisonous secretions as to the air those plants evolve.

Dr. Ingenhousz introduced leaves into glass jars filled with water, which he inverted in a tub of the same water, and placed the whole together in the sun-shine. From their under sides came streams or bubbles of air, which collected in the inverted bottom of each jar. The air thus procured proved oxygen gas,