This principal active constituent of cocoa leaves was discovered about 1860 by Niemann, and called by him cocaine. It is an alkaloid which combines with various acids in the formation of salts. It has the quality of benumbing raw and mucous surfaces, for which purpose it was applied first in 1862 by Schroff, and in 1868 by Moreno. In 1880, Van Aurap hinted that this property might some day be utilized. Karl Koller logically concluded from what was known about it that this anesthetic property could be taken advantage of for work about the eye, and made a series of experiments upon the lower animals, by which he established its efficiency and made a brilliant discovery. He reported his experiments to the Congress of German Oculists, at Heidelberg, in 1884. News of this was transmitted with great rapidity, and within a few weeks the substance was used all over the world. Its use spread rapidly to other branches of surgery, and cocaine local anesthesia became quickly an accomplished fact. More time was required to point out its disagreeable possibilities, its toxic properties and the like, but it now has an assured and most important place among anesthetic agents, and has been of the greatest use to probably 10 per cent. of the civilized world. To Koller is entirely due the credit of establishing its remarkable properties. * * * * * Transcriber's Notes Obvious typographical errors have been silently corrected, but the variations in spelling, punctuation, accents and hyphenation remain as in the original. Chapter IX The paragraph originally read: "This recognition of our profession was accorded much more unstintingly nearly two thousand years ago, at a time when it was much less deserved, when Cicero wrote (_De Natura Deorum_) "_Homines ad inibus dando._" (Men are never more godlike than when giving health to mankind)." The missing line in the Latin quotation has been restored. Italics are represented thus _italic_. End of the Project Gutenberg EBook of The Evil Eye Thanatology and Other Essays, by Roswell Park