The present treatise takes account mainly of our own persona experience, and of work done in this country, especially by members of the Factory Department of the Home Office, and certifying and appointed surgeons carrying out periodical medical examinations in lead factories. The book, however, has no official sanction. We are familiar with the immense field of Continental literature bearing on legislation against lead poisoning, but have considered any detailed reference to this outside the scope of our book, except in regard to the medical aspects of the disease. Most of the preventive measures mentioned are enforced under regulations or special rules applying to the various industries or under powers conferred by the Factory and Workshops Act, 1901. Occasionally, however, where, in the present state of knowledge, particular processes are not amenable to the measures ordinarily applied, we have suggested other possible lines on which the dangers may be met. We have not reprinted these regulations and special rules, as anyone consulting this book is sure to have access to them in the various works published on the Factory Acts. The practical value of the experimental inquiry described in Chapter VI., and the light it seems to throw on much that has been difficult to understand in the causation of lead poisoning, has led us to give the results in detail. One of us (K. W. G.) is responsible for Chapters I., III., and V. to XI., and the other (T. M. L.) for Chapters II. and XII. to XVII.; but the subject-matter in all (except Chapter VI., which is the work entirely of K. W. G.) has been worked upon by both. Our thanks are due to the Sturtevant Engineering Co., Ltd., London; Messrs. Davidson and Co., Ltd., Belfast; the Zephyr Ventilating Co., Bristol; and Messrs. Enthoven and Sons, Ltd., Limehouse, for kindly supplying us with drawings and photographs. _September, 1912._ CONTENTS CHAPTER PAGE I. HISTORICAL--CHEMISTRY OF LEAD 1 II. ÆTIOLOGY 7 III. SUSCEPTIBILITY AND IMMUNITY 27 IV. STATISTICS OF PLUMBISM 44 V. PATHOLOGY 62 VI. PATHOLOGY--_Continued_ 81 VII. SYMPTOMATOLOGY AND DIAGNOSIS 110 VIII. EXCRETION OF LEAD 127 IX. THE NERVOUS SYSTEM 140 X. CHEMICAL INVESTIGATIONS 165 XI. TREATMENT 184 XII. PREVENTIVE MEASURES AGAINST LEAD POISONING 199 XIII. PREVENTIVE MEASURES AGAINST LEAD POISONING--_Continued_ 221