CHAPTER XV.

155. Waste of Water, Particularly in the City of New York 196 156. Division of Daily Consumption in the City of New York 197 157. Daily Domestic Consumption 198 158. Incurable and Curable Wastes 199 159. Needless and Incurable Waste in City of New York 200 160. Increase in Population 200 161. Sources of Public Water-supplies 202 162. Rain-gauges and their Records 204 163. Elements of Annual and Monthly Rainfall 204 164. Hourly or Less Rates of Rainfall 207 165. Extent of Heavy Rain-storms 207 166. Provision for Low Rainfall Years 208 167. Available Portion of Rainfall or Run-off of Watersheds 209 168. Run-off of Sudbury Watershed 211 169. Run-off of Croton Watershed 211 170. Evaporation from Reservoirs 213 171. Evaporation from the Earth’s Surface 215