The old habit of Coca chewing has clung to the Peruvian Indians after their “power, civilisation, language, alphabets, writings, and even old religions have disappeared,” says Johnston,[1] “the common-life customs and the bodily features of the people have alone survived.” By him Coca is classed among the “Narcotics we indulge in,” along with Tobacco, Hop, Poppy and Lettuce, Indian Hemp, Areca or Betel-nut, Ava or Kava, Red Thorn Apple (_Datura sanguinea_) fruit, also in use among the Indians of the Andes, Siberian Fungus or Fly Agaric (_Amanita muscaria_), and Sweet Gale (_Myrica Gale_), formerly used to give bitterness and strength to the fermented liquors of the ancient Britons. But physiologists have more recently classed it with Tea, Coffee, Maté, Kola Nut, and Cocoa—the Theine- (Methyl-Theobromine) and Theobromine-yielding plants—although Cocaine has no chemical alliance with these principles. As a beverage to substitute for tea or coffee, a decoction or an infusion of Coca is worthy of attention at the present time. The Indian use of it in moderation seems to prolong life, without much need of sleep or food, or even the desire for these, although in excess it has, no doubt, a degrading effect. A taste for infusion or decoction of Coca or its pharmaceutical preparations is easily acquired; if a good sample of leaves be used it is not even at first disagreeable. [Footnote 1: “Chemistry of Common Life,” Vol. ii., p. 398.] As the plant admits of easy acclimatisation, and yields annually several crops of leaves, should it come into more extended use it is probable that its cultivation in suitable localities in mountainous parts of India, Ceylon, and Jamaica will prove a profitable enterprise to planters now commencing the growth of it. * * * * * The following abbreviations are used:— B.M.J. for _British Medical Journal_; L. for _The Lancet_; M.R. for _The London Medical Record_; M.T.G. for _The Medical Times and Gazette_; Off. for _Official_—in the _British Pharmacopæia_; P.J. for _Pharmaceutical Journal_; Pr. for _The Practitioner_. My thanks are due to my colleague, Dr. Wynn Westcott, for valuable assistance and aid in abstracting some of the references. WM. MARTINDALE. NEW CAVENDISH ST., W. _March, 1886._ PREFACE TO THE SECOND EDITION. The text has been revised; the views of physiologists, therapeutists, oculists, and surgeons generally have been brought up to date; those of chemists of the constitution of Cocaine have been epitomized, and pharmaceutical and chemical notes have been added on the modes of dispensing and testing the purity of Hydrochlorate of Cocaine. Being printed in larger type than the first edition, I trust it may be more acceptable to general medical readers. W. M. _January, 1892._ CONTENTS.