GENEEAL OBSEEVATIONS ON THE WINDS. 10^ 



Trades is in all seasons Northtvard of the Equator in the Atlantic ; and, 

 from the land influences of Africa on the N.E. Trade Wind, there is a 

 wide space of Calms, or doldrums, whose base lies against that continent, 

 with its apex stretching toward the Coast of Brasil, as may be readily seen 

 by referring to the Chart of the Winds, given in this work, which will 

 explain this peculiarity far better than any verbal description. ■) 



(14.) The Force with which the Wind blows is one of the chief consider- 

 ations of the sailor, in connection with his study of the subject. This 

 force is readily measured in a fixed observatory, or on board a ship at 

 anchor ; but not so when she is under sail, as it is manifest that she is 

 then apparently feeling less wind than is actually blowing, from being 

 drifted before it. We have had some singular accounts of some of the 

 fine clipper ships scudding at an immense rate before a gale, which has 

 been marked as of no extraordinary violence ; while other ships, dull 

 sailers, have been dismasted or disabled by the fury of the same gale, from 

 their not being able to bear away before its great velocity. Therefore, the 

 recorded force of the winds met with at sea should be subject to this 

 qualification — what are the sailing powers of the ship which has recorded 

 them ? It is manifest that a vessel, and especially a steam-vessel, will 

 estimate the force of the wind acting on her in exact proportion to the 

 direction from which she is meeting it or running before it. Thus, a vessel 

 of good sailing power going before the wind, which, while stationary, she 

 would estimate as having the force of 4, and running 5 or 6 knots before 

 it, will appear only to have a force of a light breeze, or 3 knots ; while, if 

 a steamer went 10 knots against the same wind, it would appear to blow 

 with a force of 7, or as a fresh treble-reefed topsail wind. We have no 

 standard of sea-rates for the wind as yet. It would add to the value of 

 such observations if the sailing powers of all ships engaged in adding to 

 our knowledge could be tested both when close-hauled and running free 

 upon a wind of known velocity. 



In former times the vague terms of Breeze, Gale, Hurricane, &c., sufficed 

 to describe the relative character of the wind. The late Sir Francis 

 Beaufort devised a system of simple notation which more exactly defined 

 these forces, and which is now in universal use at sea. The figures prefixed 

 indicate the estimated character of the wind* : — 



* In addition to the Jiff ures, showing the Force of the Wind, the state of the Weather 

 is to be understood by letters, as follows : — 



Letters inditating the State of the Weather (Beaufort Notation). 



b Blue Sky. 



c Clouds (detached). 



d Drizzling Rain. 



f Foggy. 



g Gloom. 



h Hail. 



1 Lightning. 



m Misty. 



Overcast. 



p Passing Showers. 



q Squally. 



r Rain. 



s Snow. 



t Thunder. 



u Ugly (threatening) ap- 

 pearance of Weather. 



V Visibility. Objects at a 

 distance unusually 

 visible. 



w Wet (Dew). 



Note. — A bar ( — 1 under any letter indicates increased intensity: — thus f very foggy, 

 r heavy rain, r heavy and continuing rain, &c., &c. 



