Isothermal charts, 63, 68-70. Isotherms, 55-57, 121. L. Land and sea breezes, 3, 131, 132. Loomis, 97, 113. M. Meteorological tables, 146-170. Mistral, 75. Monsoons, 100. Mountain and valley winds, 131. N. Nephoscope, 41-43. O. Observational meteorology, problems in, 125-141. Observations, advanced instrumental, 26-46. Observations, cloud, 5, 9, 41-43. ———— elementary instrumental, 11-26. Observations, non-instrumental, 1-10. Observations, rainfall, 9, 10, 26. ———— state of sky, 5, 9. ———— temperature, 1-3, 25. ———— wind, 3-5, 8, 9, 25. P. Pampero, 76, 104. Pascal, 21. Precipitation, 7, 9, 10, 138, 139. Pressure and wind direction, 91-93. ———— and wind velocity, 93-96. ———— atmospheric, 19-21. ———— charts, 76-83. ———— cyclonic variation of, 140, 141. ———— decrease with altitude, 139, 140. ———— diurnal variation of, 140, 141. ———— gradient, 82-85. Prevailing westerly winds, 93, 95, 96, 112, 113. Psychrometer, 28. ———— sling, 31. Purga, 75. R. Rain, see Precipitation. ———— heavy, 138, 139. ———— gauge, 15-17. Rainfall records, 17, 18, 26. S. Sensible temperatures, 29, 30. Sirocco, 103, 104, 133, 134. Sling psychrometer, 31. Smudges, 135. State of sky, 5, 9, 45. Suggestions to teachers, 171. T. Temperature charts, 58-60. ———— distribution, 51-63. ———— diurnal range, 125-127. ———— forecasts, 116. ———— gradient, 64-70. Temperature gradient, vertical, 129. ———— inversions, 129. ———— maximum and minimum, 45. ———— mean, 43, 45. ———— observations, 1-3, 8-10, 25, 43, 45. ———— range, 45, 125-127. ———— sensible, 29, 30. ———— vertical distribution of, 128, 129. Thermograph, 34-36. ———— records, 35, 36. Thermometer, 12. ———— attached, 33. ———— maximum and minimum, 26-28. ———— shelter, 13, 14. ———— wet- and dry-bulb, 28, 30, 31. Torricelli, 19, 20. Trade winds, 93. V. Veering winds, 118. Vernier, 33. Vertical temperature gradient, 129. W. Water vapor, 28. Weather, 85-90. ———— and wind direction, 106-109. ———— changes, sequence of, 113, 114. ———— charts, 85-90. Weather forecasts, 49, 114-124. ———— map data, 90. ———— maps, 47-51. ———— prognostics, 137. ———— signs, 85. ———— temperate zone, 88-90. ———— torrid zone, 88-90.