In the matter of food supply, the inhabitant of a country district is more fortunate. Fresh vegetables and dairy products are much more easily obtained, and their freshness and purity more dependable. The article on water supply by Mr. Gerhard is authoritative, written, as it is, by a most eminent sanitarian. The publishers are to be congratulated upon the following valuable contribution to the same subject as regards the use of copper sulphate and the concise presentation of plans for mosquito extermination, while the extended work of Dr. Price and Dr. Baker's "Food Adulteration" are much to be commended. The two latter have been connected with the Department of Health of New York City, and have the advantage of experience in an organization which gives to the citizens of New York the protection to health that the wise use of science, knowledge, and money afford. I trust that the notes I have added in the light of recent practice of the New York City Department of Health may make this material of the utmost practical value to the householder of to-day. Through this Department of Health, New York City spent, during 1905, over $1,500,000, and for 1906 it has appropriated over $1,800,000. This vast sum of money is used for the sole purpose of safeguarding its citizens from disease. Sanitation in its varied branches is pursued as an almost exact science, and the efforts of trained minds are constantly employed in combating disease and promoting sanitation. The cities care for their own, but the greater number of the inhabitants of this country must rely upon their individual efforts. Therefore, any dissemination of knowledge regarding sanitation is most worthy. This book has a useful mission. It is pregnant with helpful suggestions, and I most heartily commend its purpose and its contents. THOMAS DARLINGTON, _President of the Board of Health_. NEW YORK CITY. Part I WATER SUPPLY AND PURIFICATION BY WILLIAM PAUL GERHARD CHAPTER I =Country Sources of Water Supply= The writer was recently engaged to plan and install a water-supply system for a country house which had been erected and completed without any provision whatever having been made for supplying the buildings and grounds with water. The house had all the usual appointments for comfort and ample modern conveniences, but these could be used only with water borrowed from a neighbor. In all parts of the country there are numerous farm buildings which are without a proper water-supply installation. These facts are mentioned to emphasize the importance of a good water supply for the country home, and to point out that water is unquestionably the most indispensable requirement for such structures. _Adequate Water Supply Important_