38 INSTRUCTIONS TO MARINE METEOROLOGICAL OBSERVERS 



2. Let the true course and speed be WSW., 15 knots, and let the apparent 

 wind be NW. (6 points oft the bow), force 1; referring to the table we see that 

 the true direction of the wind in this case is 15 points off the liow (NE. by E.), 

 and that its true force is 4. 



A/orf/7 

 ^^20 



20 



D/recf/on anc/ l^e/oc//i/ of 

 f/je /V/nd c/ue /o f/7e /r?o//on 

 of //7e l/esse/ 



/S 20 



■-L >-,B' Tasf 



r/o 



j-ys 



S0U//7 



\ 





Figure 12. 



-True diroction and velocity of the wind deteiniined from the apparent wind 

 and motion of vessel. 



3. Let the true course and speed be E., 10 knots, the apparent wind SW. 

 (12 points off the bow), force 3. The true direction of the wind is 14 points ofE 

 the bow (WSW.), the true force is 5. 



4. Let the true course and speed be NE., 20 knots, the apparent wind SW. 

 (16 points of the bow), force G, the true direction is still SW. ; the true force, 

 however, is 9. 



WEATHER 



In tlie column headed "Present AYeather" (ww) on Form 1210A, the 

 state of the weather must be indicated by entry of one of the num- 

 bers (00 to 99) in the following code table for ww. Figures are 

 necessary in preparing the radio messages. Only one number (two 

 figures) can be sent, but more than one number for weather may 

 be entered on the form, if appropriate. If two or more numbers 

 are entered, they should be separated by dashes or written one above 

 the other. 



When two or more numbers are entered to describe the state of 

 the weather, the observer should be guided by the instructions which 

 follow in the next section as to which number is the more important 

 for the radio message ; provided, of course, that the vessel is scheduled 

 to send a report by radio. 



