Liassic clays and shales,57,125,132Lime,7,10,102,159Lime compounds,10,11,38,41,47,113,115,116,121,127,139,142,143,145,155,157,162,164Limestone,10,11,52,59,61,62,88,102,117,127,132,139Lime troubles,11Loam,57,67,88London clay,62,63,125Ludwig's chart,35Magnesium compounds,7,10,11,41,47,113,115,116,121,133,155Malm-bricks,11Malms,10,68Marcasite,10,13Marine clays,61,93Marls,10,51,54,55,57,67,68,88,130,132,166Mechanical analysis,137Medway mud,132Melting point,31,32Mica,7,8,76,104,105,116,140,141,144,160Microscopical examination,18,105,143,158Millstone grit,54,55,117Mineral nature of clay,3Minerals resembling clay,158Mining ball clay,111Modelling clays,130Moisture,15,144Molecular attraction,22Molecular constitution of clay,21,156Montmorillonite,134Mundic,13Muscovite,105Newtonite,158Nodules,121,127Non-plastic material,43,121,151Non-refractory clays,166Occurrence of clays,48,116Ocean currents, action of,89Odour of clay,19Oil, bleaching,134Oil shales,61,122,123Oolite clays,59,134Ooze,95,99Organic matter,19,119Origins of clays,48,71,160,165Oxford clay,59,95,164Oxides in clay,10,82Paint, clays for,109Paper, clays for,109Particles, nature of,18,31,106,107,150Paving brick clays,166Pelagic ooze,95,99Pelinite,83,148,149Permian clays and shales,57,112,124Pholerite,117Physical characters of clays,17Picking clay,121Pipe clays,64,65,82,109,166Plant-extracts in clays,26Plastic clays,2,43,65,67,82,88,102,112,123,147,148,160Plasticity,20-27,41,46,97,98,99,108,109,112,117,123,125,127,151,160Pleistocene clays,67Pockets,65,85,101,116,166Porcelain,37,46,73,109,110,125,129Pores in clay,30,114Porosity,30,39,121,131,155Portland cement,131Potash compounds,7,10,113,115,116,121,157,seeAlkaliesPottery clays,1,5,31,46,66,100, 101,104,110,112,114,125,129,162,166Precambrian clays,51Precipitated clays,97,152Primary clays,70,71,84,165Proximate analysis,16,144Purbeck clays,59Pure clays,5,6,7,142,155,156Purification of clay,7,66,78,104,113,128,140Pyrites,10,13,44,56,57,119,124,128Quartz,8,104,110,118,140,141,143Rain,44,85,86Rational analysis,141Reading clays,63Recent clays,67Rectorite,158Re-deposited clays,98Red bricks,12Red burning clays,141,142,166Red iron oxide,12Red ware,113Reduction in volume,30Refractoriness,34,119,120,123,155Refractory articles,5,119Refractory clays,9,32,33,35,38,52,65,82,104,116,165,166Residual clays,70,84,166Resistance to abrasion,119Resistance to corrosion,119Resistance to crushing,46Resistance to cutting,119Resistance to temperature, seeRefractorinessResistance to weathering,76Ringing sound,110River-deposited clays,88Rivers,85,87Rock binds,53Rockingham,113Rock-like clays,2Rocks associated with clay,48Roman cements,133Roofing tiles,57,63,126,128Sagger marls,54Sand,7,31,41,62,82,89,100,101,117,133,138,144Sandstones,53Sandy clays,68Sandy loams,88Sandy marls,88Sanitary articles,5,113Sawdust,40Scum,10Sea, action of,85,89,99Sea-deposited clays,93Secondary clays,70,82,83,166Sedimentary rocks,48Sedimentation of clay,43,88,90,104Seger cones,33,34Selection of clay,122Selenite,10Separation of clays,90,145Settling,43Sewerage pipes,113Shale oil,15,61Shale tar,123Shales,2,5,51,52,53,57,61,96,104,122,130,132,138,151,162,166Shrinkage,11,29,58,68,102,110,117,119,121,127,131,153Sifting,7,138Silica,6,7,80,154,155,161Silica rock,118Silicates,8,82Siliceous clays,117Sillimanite,46,154Silt,90,91,99,139,144Silurian clays and shales,51,124Sintering,38Size of particles,18,21,31,106,107,150'Skeleton,' 115'Skin' on ware,131Slag in bricks, etc.11,13,119,155Slates,51Slurry,39,43,152Snow,85Soda compounds,7,10,113,115,116,121,157,seeAlkaliesSoftening point,33Soil, seeAgricultureSolubility of clay,151,159Soluble salts,10Sorting,90Sources of clays,85Specification of fire clays,120Specific gravity,18,106,151Staffordshire bricks,13,56Standard clay,4Stone, Cornish,110,116Stoneware clays,104,112,113,156,165,166Stones,7,65,100,102,128,138,144Streams,85,86Strength,23,45,113Sub-surface clays,5Sulphates in clay,10,12,82Sulphides in clay,10,82Sulphuric acid,124Sunlight,45Surface clays,2,5,52,112Suspension of clay,43,90,140,152Swelling,15,102Tannin in clay,25,26,41Telluric water,165Temperature, resistance to,119,120Tensile strength,23,45Terra-cotta clays and shales,5,10,12,31,46,56,63,91,104,123,124,129,166Tertiary clays,62Texture,112,130Thermal reactions,146,154,158Tiles,1,5,57,91,101,129Titanium compounds,121Tourmaline,76,104Transportation of clays,49,86,98,99,100Transported clays,70Triassic clays,57,112,130True clay,144,146,149,150,160Twisted ware,114,129,131Types of clay,82Ultimate analysis,16,144Ultra-marine, clays for,109Underclays,53,117,118Uses of clay,1,165Valuation of clay,103,109,123,126,162,165Vegetable matter,15,119Veins,85Viscosity,152Verifiable clays,113,156,166Vitrification,15,20,37,112,113,114,156Vitrification range,38,114,115,116,
Liassic clays and shales,57,125,132Lime,7,10,102,159Lime compounds,10,11,38,41,47,113,115,116,121,127,139,142,143,145,155,157,162,164Limestone,10,11,52,59,61,62,88,102,117,127,132,139Lime troubles,11Loam,57,67,88London clay,62,63,125Ludwig's chart,35Magnesium compounds,7,10,11,41,47,113,115,116,121,133,155Malm-bricks,11Malms,10,68Marcasite,10,13Marine clays,61,93Marls,10,51,54,55,57,67,68,88,130,132,166Mechanical analysis,137Medway mud,132Melting point,31,32Mica,7,8,76,104,105,116,140,141,144,160Microscopical examination,18,105,143,158Millstone grit,54,55,117Mineral nature of clay,3Minerals resembling clay,158Mining ball clay,111Modelling clays,130Moisture,15,144Molecular attraction,22Molecular constitution of clay,21,156Montmorillonite,134Mundic,13Muscovite,105Newtonite,158Nodules,121,127Non-plastic material,43,121,151Non-refractory clays,166Occurrence of clays,48,116Ocean currents, action of,89Odour of clay,19Oil, bleaching,134Oil shales,61,122,123Oolite clays,59,134Ooze,95,99Organic matter,19,119Origins of clays,48,71,160,165Oxford clay,59,95,164Oxides in clay,10,82Paint, clays for,109Paper, clays for,109Particles, nature of,18,31,106,107,150Paving brick clays,166Pelagic ooze,95,99Pelinite,83,148,149Permian clays and shales,57,112,124Pholerite,117Physical characters of clays,17Picking clay,121Pipe clays,64,65,82,109,166Plant-extracts in clays,26Plastic clays,2,43,65,67,82,88,102,112,123,147,148,160Plasticity,20-27,41,46,97,98,99,108,109,112,117,123,125,127,151,160Pleistocene clays,67Pockets,65,85,101,116,166Porcelain,37,46,73,109,110,125,129Pores in clay,30,114Porosity,30,39,121,131,155Portland cement,131Potash compounds,7,10,113,115,116,121,157,seeAlkaliesPottery clays,1,5,31,46,66,100, 101,104,110,112,114,125,129,162,166Precambrian clays,51Precipitated clays,97,152Primary clays,70,71,84,165Proximate analysis,16,144Purbeck clays,59Pure clays,5,6,7,142,155,156Purification of clay,7,66,78,104,113,128,140Pyrites,10,13,44,56,57,119,124,128Quartz,8,104,110,118,140,141,143Rain,44,85,86Rational analysis,141Reading clays,63Recent clays,67Rectorite,158Re-deposited clays,98Red bricks,12Red burning clays,141,142,166Red iron oxide,12Red ware,113Reduction in volume,30Refractoriness,34,119,120,123,155Refractory articles,5,119Refractory clays,9,32,33,35,38,52,65,82,104,116,165,166Residual clays,70,84,166Resistance to abrasion,119Resistance to corrosion,119Resistance to crushing,46Resistance to cutting,119Resistance to temperature, seeRefractorinessResistance to weathering,76Ringing sound,110River-deposited clays,88Rivers,85,87Rock binds,53Rockingham,113Rock-like clays,2Rocks associated with clay,48Roman cements,133Roofing tiles,57,63,126,128Sagger marls,54Sand,7,31,41,62,82,89,100,101,117,133,138,144Sandstones,53Sandy clays,68Sandy loams,88Sandy marls,88Sanitary articles,5,113Sawdust,40Scum,10Sea, action of,85,89,99Sea-deposited clays,93Secondary clays,70,82,83,166Sedimentary rocks,48Sedimentation of clay,43,88,90,104Seger cones,33,34Selection of clay,122Selenite,10Separation of clays,90,145Settling,43Sewerage pipes,113Shale oil,15,61Shale tar,123Shales,2,5,51,52,53,57,61,96,104,122,130,132,138,151,162,166Shrinkage,11,29,58,68,102,110,117,119,121,127,131,153Sifting,7,138Silica,6,7,80,154,155,161Silica rock,118Silicates,8,82Siliceous clays,117Sillimanite,46,154Silt,90,91,99,139,144Silurian clays and shales,51,124Sintering,38Size of particles,18,21,31,106,107,150'Skeleton,' 115'Skin' on ware,131Slag in bricks, etc.11,13,119,155Slates,51Slurry,39,43,152Snow,85Soda compounds,7,10,113,115,116,121,157,seeAlkaliesSoftening point,33Soil, seeAgricultureSolubility of clay,151,159Soluble salts,10Sorting,90Sources of clays,85Specification of fire clays,120Specific gravity,18,106,151Staffordshire bricks,13,56Standard clay,4Stone, Cornish,110,116Stoneware clays,104,112,113,156,165,166Stones,7,65,100,102,128,138,144Streams,85,86Strength,23,45,113Sub-surface clays,5Sulphates in clay,10,12,82Sulphides in clay,10,82Sulphuric acid,124Sunlight,45Surface clays,2,5,52,112Suspension of clay,43,90,140,152Swelling,15,102Tannin in clay,25,26,41Telluric water,165Temperature, resistance to,119,120Tensile strength,23,45Terra-cotta clays and shales,5,10,12,31,46,56,63,91,104,123,124,129,166Tertiary clays,62Texture,112,130Thermal reactions,146,154,158Tiles,1,5,57,91,101,129Titanium compounds,121Tourmaline,76,104Transportation of clays,49,86,98,99,100Transported clays,70Triassic clays,57,112,130True clay,144,146,149,150,160Twisted ware,114,129,131Types of clay,82Ultimate analysis,16,144Ultra-marine, clays for,109Underclays,53,117,118Uses of clay,1,165Valuation of clay,103,109,123,126,162,165Vegetable matter,15,119Veins,85Viscosity,152Verifiable clays,113,156,166Vitrification,15,20,37,112,113,114,156Vitrification range,38,114,115,116,