VUl 



CONTENTS. 



ty 



97. Terrestrial magnetism : total intensity 



98. " " secular change of total intens 



99. " " agonic line . 

 100. Magnetic elements at magnetic observatories 

 loi. Pressure of mercury and water columns 



102. Reduction of barometer to standard temperature 



103. " " " " " gravity, inch and metric scales 



104. " " *' " latitude 45° : inch scale 



105. " " " " " " metric scale 



106. Correction of barometer for capillarity : inch and metric scale . 



107. Volume of mercury meniscus in cu. mm. ..... 



108. Aerodynamics : data for wind pressures 



109. " " " the soaring of planes .... 

 no. Coefficients of friction . . 



111. Lubricants 



112. " for cutting tools 



113. a Viscosity of water at different temperatures .... 

 b Specific viscosity of water at different temperatures 



114. Coefficients of viscosity for solutions of alcohol in water . 



115. Specific viscosity of mineral oils 



116. " " " various oils 



117. Viscosity of various liquids 



118. " " " " temperature variation 



119. Specific viscosity of solutions : variation with density and temperature 



120. " " " " atomic concentrations 



121. Viscosity of gases and vapors 



122. " " air 2o?2 C 



123. " " gases and vapors, temperature variation . 



124. Diffusion of an aqueous solution into pure water 



125. " *' vapors 



126. " " gases and vapors 



127. " " metals into metals 



128. Solubility of inorganic salts in water : temperature variation 



129. " ** a few organic salts in water : temperature variation 



130. " " gases in water 



131. " , change produced by uniform pressure 

 T32. Absorption of gases by liquids 



133. Capillarity and surface tension : water and alcohol in air . 



134. " " " " miscellaneous liquids in air 



135. " " " " aqueous solutions of salts . 



136. Capillarity and surface tension : liquids in contact with air, water or 



mercury .......... 



137. Capillarity and surface tension : liquids at solidifying point 



138. " " *' " thickness of soap films 



139. Vapor pressures 



140. " " of ethyl alcohol 



