A HANDBOOK OF HYGIENE AND SANITARY SCIENCE BY GEORGE WILSON, M.A., M.D. & C.M. (EDIN.), F.C.S. MEDICAL OFFICER OF HEALTH FOR THE MID-WARWICKSHIRE SANITARY DISTRICT FORMERLY MEDICAL OFFICER H.M. CONVICT PRISON, PORTSMOUTH THIRD EDITION GREATLY ENLARGED, AND IN MANY PARTS RE-WRITTEN PREFACE TO THE THIRD EDITION. THE first edition of this work, which appeared not long after the passing of the Public Health Act 1872, was so favourably received that a second was called for within six months, and this too has been out of print for nearly a year. The delay in the preparation of the present edition, although to me a matter of deep regret, is in great measure due to my desire to make the work still more worthy of continued confidence, and to spare no pains in incorporating all the more important facts and details connected with the recent rapid progress of sanitary science. In the preface to the first edition I expressed my great indebtedness to the standard work of the late Dr. Parkes, and I wish now to acknowledge what his own kindliness of heart and diffident nature would not permit me to acknowledge before-that it was under his encouragement that the work was first written, and that all the proof-sheets were submitted to him at his own request as they issued from the press. To an untried author in sanitary science such counsel as his was invaluable; and though I might eulogise his memory in other and more eloquent terms, I cannot do so more sincerely than by expressing, in this simple way, my heartfelt obligations to him, which never can be forgotten. Amongst other numerous works which I consulted in the preparation of the first edition, I desire especially to mention Mr. Simon's Reports to the Privy Council; Dr. Letheby's work on food; Captain Douglas Galton's work on the construction of hospitals; and the writings of Dr. Carpenter, Dr. Angus Smith, Dr. Hassall, Mr. Rawlinson, Mr. Eassie, and Professor Rankine. Full acknowledgment of other authors is given in the proper places. In the preparation of the present edition I have to acknowledge my obligations to the Sanitary Record, Public Health, Lancet, British Medical Journal, Medical Times and Gazette, Practitioner, and, more especially with regard to systematic details and authentic information of all kinds, to Mr. Simon's new series of Reports to the Local Government Board, the Sixth Report of the Rivers' Pollution Commissioners, and the more recent Reports of the State Board of Health of Massachusetts. Every chapter has been carefully revised and amended, several have been entirely re-written, and a |