I have been thus minute in specifying the details of the plan of inspection, the qualifications of the Inspectors, and the means employed, in order that the character of the work and the value of the results obtained may be properly appreciated. [Sidenote: Period of the Inspection] Early in the month of May the work of thoroughly inspecting the insalubrious quarters, where fever and other pestilential diseases prevail, had been commenced, and the fact was soon ascertained that smallpox and typhus fever were existing and spreading in almost every crowded locality of the city. It was not until about the middle of July that the entire corps of Inspectors was engaged. The work was then prosecuted with vigor and without interruption to the middle of November, when it was completed. The Inspectors met regularly every Saturday evening to report to a committee on the part of the Council the progress of their work, and to receive advice and instruction in regard to all questions of a doubtful character. On the completion of the inspection each Inspector was required to prepare a final report embodying the general results of his labors. These reports have all been properly collated, under the direction of the Association, and are now passing through the press. They will soon appear in an octavo volume of about 400 pages, largely illustrated, with maps and diagrams. It will be the first interior view of the sanitary and social condition of the population of New York, and will abundantly demonstrate the fact that, though a great and prosperous commercial centre, she does not afford happy homes to hundreds of thousands. [Sidenote: Distribution of Population] Before proceeding to an analysis of this work, it will be necessary to notice the topographical peculiarities of our city, and the distribution of its population. New York is an island having an area of about thirty-four square miles, inclusive of its parks. Unlike Philadelphia, London, and most other large cities, which have a background of hundreds of square miles upon which to extend according to the exigencies of the population or of business, New York is limited in its power of expansion, and must accommodate itself to its given area. While it is true that a large business population will gather upon the adjacent shores, it is equally true that these non-residents will be of the better class. The laboring population will, for the most part, remain upon the island, and must be accommodated in the city proper, as they are compelled to live near their work.