Water,

depth, 483

disruptive force of, freezing, 455

Water-proofing, 189, 390

concrete bridges, 451

cost of, 450

definition, 449

deterioration, 452

economics, 449-458

material for decks, 183

material must be elastic, 452

original cost, 450

probable life, 451

slabs, 454

value of, 452

Waterway, clear, 122

obstruction of, by pier shafts, 170

Weakness in old bridges, 414

Wearing of pins, 415, 423

Wearing out of steel structures, 423

Web splices, 207

Web thickness, 207

Weights,

alloy-steel eye-bars in

suspension-bridges, 277

arch bridges, approximate

formulae for, 248

arches compared to weights of

trusses, 238, 239

deck reduced to minimum, 194

metal in arches, formulae

for, 239, 240

metal in cantilever bridges, 31

metal to carry one pound

of load, 196, 197

stiffening trusses, 93

Welsh, Ashbel, 14

economic comparison, 14

West Point, Ga., crossing of the

Chattahoochee River, 471

Western Society of Engineers, 90, 112,

268

paper presented to, 150

Wharves, 384

Wide range of economic limits, 16

Widths,

decks, 126-128

footwalks, 128

roadway for military bridges, 473, 474

stream, 483

structure in cantilever and

suspension bridges, 94

Wind loads, unit, 316

Wind pressure,

bascules, 316

effect on moving spans, 293

unbalanced, 315

Winner Bridge, 169

Wolfel, Paul L., 214

Wood preservation, 419

Wooden,

block pavements, 426

piles versus reinforced-concrete

piles, 174

stringers undesirable, 425

ties for street car traffic, 425

Work of Engineer, importance of, 3

Work, unclassified, 381

Working full time, necessity for, 2

Working stresses,

concrete, intensities of, 219

determination of, 132

heat-treated steel, 37

old bridges, limiting, 410, 411

tension and compression,

relation of, 136

Workmen,

force of, 373

sharing profits with, 338, 370

Worm gearing, 313

Wrecks encountered in sinking, 172

Writings, author's, on bridge

economics, 489

Y

Yards, 384

Yates, J. J., 395