lling instrument, (illustration), 52
Levelling rod, (illustration), 53
Location of main drains, 58

Madden, Dr., quotation from, 12
Main drain, 96
Main drain, location of, 58
Malaria 211
Malaria borne by winds, 212-214-219
Malaria conclusions of the General Board of Health of England, 220
Malaria facts concerning, 212
Malaria spread of, prevented by hills, 218
Malarial diseases, evidence of the effect of drainage in removing,
216
Malarial diseases, reports to the British Parliament concerning, 216
Malarial diseases, rheumatism and tic-douloureux, 219
Malarious localities, effects of residence in, 214
Maps, amending the, 142
Maps, description of, (illustrations), 49-50-51-54-98
Maps, importance of, 48
Marking the lines, 116
Mechi, Alderman, quotations from, 29-71
Mellowness or Porosity, 41
Measuring staff (illustration), 124
Metcalf, Dr., quotation from, 211
Movement of water in the ground, 32-64-65
Mortality, rate of reduced by improved house drainage, 222

Neuralgia, 208
New York, suggestions for sewer outlets, 227

Oats, 168
Obstructions, 90
Opening ditches, 122
Outlet, 95
Outlet, how made (with illustrations), 118
Outlet, location of, 58

Parkes, Josiah, quotations from, 36-71-88-178
Porosity, 41
Profile of a drain, (illustration), 106
Profit, instances of, 167-170
Production, amount of increase of, necessary to make draining
profitable, 162
Puddling, 8-31-148
Pumping, 206
Pumping, London sewage, 226

Rock, sounding for, 55
Rock, how to collect water from, 60
Roots, depth to which they reach, 40-67
Roots, as a cause of obstruction, 93-148
Rye, 168

Salisbury's, Dr., theory concerning malarious fever, 214
Salt marshes, catch water drains, 201
Salt marshes, construction of embankment, 196
Salt marshes, dyke and ditch, (illustration), 197
Salt marshes, exclusion of the sea, 195
Salt marshes, how formed, 194
Salt marshes, inundations from upland , 201
Salt marshes, location and size of embankment, 195
Salt marshes, management of creeks, 198-200
Salt marshes, management of rivers, 201
Salt marshes, muskrats, 199
Salt marshes, outlet for under dr