WEATHER OBSERVATIONS 147 



c. 1302 : 279. Private Weather Observations. 



d. 1303 : 81-82. Weather Predictions. 



e. 1307 : 264-266. Weather Forecasting. 



/. 1309 : 237-238. Weather Forecasts and the Weather Maps. 



g. 1310 : 402-430. Weather Maps. 



h. 1311 : 246-247. The Mapping of Temperature. 



i. 1312:390-393. Weather Maps. 



3. Weather Bureau. Explanation of the Weather Map. 

 Reprints from Yearbook of Department of Agriculture. 



4. 1900. Amplification of Weather Forecasts. 



5. 1906. New Problems of the Weather. 



6. 1907. The Weather Bureau and the Public 



Schools. 



Experiment 56. Temperature Curves. 



Apparatus : Thermometer. 



Materials : Cross-section paper. (Sections about J inch 

 square.) 



a. Take thermometer home and record readings of tem- 

 perature every hour from 7 A.M. to 8 P.M. 



6. Place the cross-section paper with the long side next to 

 you and mark off the hours on every other line beginning 

 with 6 A.M. and ending with 9 P.M. On the left side of the 

 paper mark off the temperatures, beginning at a temperature 

 5 below the lowest reading which you took. Use one square 

 for each degree. On the 7 A.M. line make a cross opposite 

 the reading for that time. Use the same method for successive 

 hours. Now run a smooth curve through all of the crosses, 

 and the temperature curve is finished. 



c. What was the temperature at 9.30 A.M.? Obtain the 

 information from your curve. This is an example of inter- 

 polation. What was the temperature at 6 A.M.? Extend 

 the curve in the way in which it would seem to go naturally. 

 This is an example of exter potation. 



