MESSAGE.

Gentlemen of the Common Council:

The City Charter requires an Annual Message from the Mayor and Reports from the City Departments. The intention of the requirement is to furnish information to our constituents, as well as to afford material for the practical co-operation of city officials.

Copies of these Annual Reports are hereto annexed. They end as nearly to the close of the municipal year (1870-71, April) as it is possible to conform their narrative or statistics to a period which best agrees with the system of work established by each Department for its own convenience. They are thorough in information, and do not need elucidation or explanation.

Before proceeding to general comments, a few statistics should be premised. New York island has an area of twenty-two square miles and twenty-nine miles of water front, about three fourths of which stretches along the Hudson and East rivers and the remaining one fourth upon the Harlem river and Spuyten Duyvil creek. The streets, roads, and avenues measure four hundred and sixty miles. Two hundred and ninety-one miles of these are paved; one hundred and sixty-nine miles are unpaved. Nineteen thousand gas-lights are burned every night at the public expense to light this area, water front, and extent of streets. Beneath the surface of the city there are three hundred and forty miles of Croton water pipes and two hundred and seventy five miles of sewers. If we accept the last Federal census, the number of our constituents is nine hundred and forty-two thousand two hundred and fifty-two. One thousand horse railway cars, two hundred and sixty-seven omnibuses, about twelve thousand licensed vehicles, aud quite as many more private