ion in water, and by combined works, should be applied to all
houses, especially those occupied by the poorer classes."

Later investigations of the subject have established two general
conclusions applicable to the subject, namely, that:

"_In towns all offensive smells from the decomposition of animal and
vegetable matter, indicate the generation and presence of the causes of
insalubrity and of preventable disease, at the same time that they prove
defective local administration;_ and correlatively, that:

"_In rural districts all continuous offensive smells from animal and
vegetable decomposition, indicate preventable loss of fertilizing matter,
loss of money, and bad husbandry._"

The principles herein set forth, whether relating to sanitary improvement,
to convenience and decency of living, or to the use of waste matters of
houses in agricultural improvement, are no less applicable in America than
elsewhere; and the more general adoption of improved house drainage and
sewerage, and of the use of sewage matters in agriculture, would add to
the health and prosperity of its people, and would indicate a great
advance in civilization.

INDEX

Absorption and Filtration, 26-39
Angles to be, as far as possible, avoided, 99

Baking of clay soils by evaporation, 30
Barley, 168
Bartlett, Dr., quotation from, 211
Base-line, 145
Boning-rods, (with illustrations), 125-126

Central Park, 74-86
Cess-pools, cause of epidemics, 237
Chadwick, Dr., quotation from, 213
Clay Soils, 75
Clay Soils, Baking of by Evaporation, 30
Clay Soils, Made mellow by draining, 29-30
Clay Soils, Shrinkage of, 28
Clinometer, (illustration), 56
Collars, 84
Connections, 132
Connections (illustrations), 134
Corn, Indian, 162
Cost of draining, 150-153-158
Cotton, 169
Covering and filling, cost of, 157
Covering for the joints of tiles, 132
Covering tiles, 136

Datum-line, 52-104
Denton, J. Bailey, quotation from, 115
Distance between drains, 73
Diseases, malarial, 208
Ditches, cost of digging, 154
Draining, amateur, 47
Draining, indications of the need of, 9
Draining, its effect on farming, 171
Draining, tiles, how made, 174
Draining, tiles, materials for, 174
Draining, tools, (illustration), 114
Draining, what