VI CONTENTS
Part III. Nonmetals:  Page
  *~Abrasive materials, by Robert W. Metcalf  1339
  t,Asbestos, by Oliver Bowles and A. C. Petron  14~27
   Asphalt and related bitumens, by A. H. Redfield  1183
   Barite, witherite, and barium chemicals, by Bertrand L. Johnson and
    K. G. Warner  1439
  ~Carbon black, by G. R. Hopkins and H. Backus  1171
   Cement, by Oliver Bowles and E. V. Balser  1191
   Clays, by Paul M. Tyler and A. Linn -. 1321
Coal:
    Bituminous coal and lignite 811
    Pennsylvania anthracite, by J. A. Corgan, Robert H. Ridgway,
      and A. V. Coleman 903
 Coke and byproducts, by Robert H. Ridgway, J. A. De Carlo, and
   M. M. Otero 943
 Crude petroleum and petroleum products, by A. G. White, G. R.
   Hopkins, H. A. Breakey, and A. T. Coumbe 1021
 Cryolite and fluorspar, by H. W. Davis 1399
 Feldspar, by Robert W. Metcalf 1417
L_—Fluorsparandcryolite,byH.W.Davis 1399
 Fuel briquets and packaged fuel, by G. S. Goodman  999
Gem stones, by Sidney H. Ball 1517
Gravel and sand, by OliverBowles and G. E. Tucker 1271
Ground soapstone, talc, and pyrophyilite, by Bertrand L. Johnson ~nd
K. G. Warner 1389
L-Gypsum. by Forrest T. Moyer 1291
Helium, by H. S. Kennedy and R. A. Cattell 1179
i_Lime, by Oliver Bowles and F. D. Gradij.an 1303
Liquefied petroleum gases and natural gasoline, by F. S. Lott and
A. T. Coumbe 1153
Magnesium compounds and miscellaneous salines, by Alvin Scliallis
K. G. Warner 1497
&~—.Mica, by Paul M. Tyler and K. G. Warner 1465
Minor nonmetals, by Paul M. Tyler and Charles L. Harness 1529
Natural gas, by F. S. Lott and G. R. Hopkins 1115
Natural gasoline and liquefied petroleum gases, by F. S. Lott and
A. T. Coumbe 1153
Packaged fuel and fuel briquets, by G~ S. Goodman 999
Peat, by Joseph A. Corgan 1017
Petroleum products and crude petroleum, by A. G. White, G. R.
Hopkins, H. A. Breakey, and A. T. Coumbe 1021
Phosphate rock, by Bertrand L. Johnson and K. G. Warner 1371
~-. Potash, by J. H. Hedges 1451
Pyrites and sulfur, by Allan F. Matthews and A. W. Mitchell 1357
Pyrophyllite, ground soapstone, and talc, by Bertrand L. Johnson and
K. G. Warner 1389
Salt, by F. E. Harris and K. G. Warner 1483
Sand and gravel, by Oliver Bowles and G. E. Tucker 1271
Slate, by Oliver Bowles and M. S. Jensen 1263
Stone, by Oliver Bowles and M. S. ,Jensen 1225
L. Sulfur and pyrites, by Allan F. Matthews and A. W. Mitchell       1357
Talc, pyrophyllite, and ground soapstone, by Bertrand L. Johnson and
    K. G. Warner 1389
 ~_ Witherite, barium chemicals, and barite, by Bertrand L. Johnson and
    K. G. Warner 1439
Part IV. Mine safety:
   Employment and accidents in the mineral industries, by W. W.
    Adams 1539
Index, by M. E. Winslow 1551