viii CONTENTS. 



74. Woods: hardwoods, English units 98 



75. " conifers, English units 99 



76. Rigidity Modulus 100 



77. Variation of moduli of rigidity with the temperature 100 



78. Interior friction, variation with the temperature 101 



79. Hardness 101 



80. Relative hardness of the elements 101 



81. Poisson's ratio 101 



82. Elastic moduli of crystals, formulae 102 



83. " ' " " " numerical results 103 



COMPRESSIBILITY OF GASES 



84. Compressibility of O, air, N, H, different pressures and temperatures . 104 



85. " " ethylene at " " . 104 



86. Relative gas volumes at various pressures, H, N, air, O, CC>2 .... 104 



87. Compressibility of carbon dioxide, pressure- temperature variation . . 105 



88. " gases, values of 105 



89. " air and oxygen between 1 8 and 22 C 105 



90. Relation between pressure, temperature and volume of sulphur dioxide 106 



91. " " " " " " " ammonia . . . 106 



92. Compressibility of liquids 107 



93. " " solids 108 



DENSITIES 



94. Specific gravities corresponding to the Baume scale 109 



95. Densities of the solid and liquid elements no 



96. " various woods 112 



97. " " " solids 113 



98. " " alloys 114 



99. natural and artificial minerals 115 



100. " molten tin and tin-lead eutectic 115 



101. Weight in grams per square meter of sheet metal 116 



102. " various common units of sheet metal 116 



103. Densities of various liquids 117 



104. Density of air-free water between o and 41 C 118 



105. Relative volume of water between o and 40 C 119 



106. Density and volume of water, 10 to 250 C 120 



107. " " " " mercury, -10 to 360 C 121 



108. Density of aqueous solutions of salts, bases and acids 122 



109. ethyl alcohol, temperature variation 124 



no. methyl alcohol, cane-sugar, sulphuric acid . ... 126 



in. " various gases 127 



112. Volume of gases, values of i + 0.00367 /: 



(a) for values of t between o and 10 C by o. i steps .... 128 



(b) " " "" " -90 and +1990 C by 10 steps . 129 



