81.

Grade, for house drains, 45;
for cellar drains, 51;
of subsurface tile, 222.

Ground water, 43.

Growth of mosquitoes, 384.

Habit and food, 267.

Hand basin in bath-room, 199.

Hands to be washed frequently, 287.

Hand valves for sewage tanks 227.

Hard water, 133.

Health departments, 416.

Heat, and plumbing, 190;
as a disinfectant, 327.

Heating and ventilation, 87.

Heredity and health, 298.

Homer, N. Y., water-supply, 105.

Hookworm disease, 302, 388.

Hot-air engines for pumping, 175.

Hot-water boiler, 198.

Hot-water circulation, 194.

House drainage, 200.

House drains, 44.

Hydraulic rams, 171.

Hydrophobia, 407.

Hygiene, and its laws, 410;
and its true purpose, 23.

Ice and typhoid fever, 353.

Ideality of life, 22.

Immunity--natural and artificial, 310.

Importance of bacteria, 305.

Impurity of surface water-supply, 140.

Indians and ventilation, 74.

Indirect causes of death, 312.

Infection in pneumonia, 348.

Influenza in the country, 19.

Inlet for fresh air, 78, 81.

Inspection of dairies, 421.

Installation of plumbing, 189.

Intermittent application of sewage on land, 213.

Iron pipe for conveying water, 167.

Irrigation and sickness, 36.

Irritation of cell tissue, 297.

Ithaca typhoid epidemic, 354.

Joints in soil-pipe, 203;
in tile pipe, 167.

Kerosene and mosquitoes, 383.

Kewanee Water Supply Co. tanks, 187.

King of ventilation, 86.

King's experiments on ventilation, 70.

Kitchen sinks, 196.

Kitchen stove and hot water, 195.

Koch and consumption, 333.

Land treatment of sewage, 216

Laundry tubs, 196.

Law and hygiene, 410.

Laws against impure food, 416.

Lesions of tuberculosis, 252.

Level for house drain, 200.

Light, as a disinfectant, 330;
in cow stables, 62.

Lime for disinfecting, 324.

Liquid disinfectant, 321.

Location, of a house, 29;
of a house on a side hill, 32;
of privies and cesspools, 31;
of windmill, 171.

Long Island wells, 112.

Loss of head by friction, 129.

Lowell typhoid epidemic, 355.

Lungs, air required by the, 68;
developed by exercise, 279.

Made ground and health, 37.

Malaria, 302, 377;
caused by soil formation, 33;
from cellars, 39.

Malarial attacks, 385.

Manure from cow stables, 244.

Maximum rate of water consumption, 95.

Measles, and its virulence, 371;
preliminary symptoms, 367.

Meat and its da