320 SUGGESTIONS FOR WEATHER STUDY. 



Cyclones and Anticyclones. 



For senior pupils exercises in the charting of the weather 

 over a large area should be given. This kind of exercise 

 is valuable in demonstrating to the pupils the existence of 

 cyclones and anticyclones, and in rendering them familiar 

 with the general basis upon which weather forecasting is 

 carried out. Two exercises of this kind are appended, one 

 to illustrate the existence of a cyclone, and the other of an 

 anticyclone. 



Maps for the purpose of weather charting on these lines 

 may be bought very cheaply from the Meteorological Office, 

 63 Victoria Street, London. Their official designation is 

 M.O. Form 227. 



Fig. 171 represents this map reduced to a scale of f, 

 with some of the details omitted. It shows the various 

 meteorological stations in Western Europe where the 

 records are taken of height of barometer, direction and 

 force of wind, etc., from which the weather forecasts are 

 prepared. The direction and force of the wind are indi- 

 cated on the chart by means of various types of arrows as 

 shown in the "explanations " on Figs. 172, 173. 



Exercise. 



From the data supplied on p. 321 fill in upon the map in 

 clear figures and symbols the barometric pressure, direction 

 and force of wind at the stations shown. Connect by 

 isobaric lines the regions of equal pressure. The lines need 

 not be carried directly through the stations upon the map, 

 but when the general line of equal pressure has been de- 

 termined by a careful examination of the figures entered 

 on the map it should be indicated by a sweeping curve 

 along it (see Figs. 172, 173). 



