THE ANTI-TEADES OB PASSAGE WINDS. 171 



Trades. This was alluded to in the Section on Atlantic Weather (pages 

 124 — 128), and will be further discussed, together with the rotatory nature 

 of such storms. The reader is also advised to refer to Section 2, on the 

 Motions and Pressure of the Atmosphere, where full particulars will be 

 found of the causes which lead to the appearance ot these storms. 



(104.) The most accurate and extensive observations — extensive because 

 continuous — which have been made upon the direction and force of the 

 wind in these latitudes, are those made upon land, and especially by self- 

 registering instruments, which have been in operation for a series of years, 

 and give absolutely the quantity and path of the wind passing over the 

 observatory during their operation. But these observations, however ex- 

 cellent, are fallacious; they do not give the correct normal direction of the 

 wmd, but that of the wind under the powerful influence of the adjacent 

 land and its configurations. This may be obviated by the erection of 

 anemometers on isolated spots, as was done at Bermuda, or any other 

 position distant from any great mass of land.* 



(105.) The Westerly predominance of the Anti -Trades will be more 

 manifest from an examination of the quantity (or force) ot the wind, 

 rather than its prevalence, from those quarters ; so that mere numerical 

 preponderance gives an imperfect notion of the real proportion of Westerly or 

 Easterly winds. Thus, as before remarked (*) on page 133, the Pilot Charts 

 of Captain Maury and others, though the result of vast labour and of the 

 first importance as grand repertories of facts, are deficient in this respect. 

 A perfect Wind Chart is yet to be constructed. 



(106.) But there have been numerous analyses of these Wind Charts, 

 combined with observations derived from other sources. We need not 

 further allude to the series of Wind Charts drawn up from Captain Maury's 

 numerical data by Admiral FitzEoy, nor of those arranged by the Nether- 

 lands Meteorological Institute at Utrecht, and others previously mentioned 

 (page 125). But there is one essay which is of much importance, published 

 by the Hamburg Meteorological Office (Norddeutsche Seewarte), and trans- 

 lated by our own Meteorological Department, in 1872. It was drawn up 

 by Herr von W. von Freeden, Director of that Office, f and is entitled, 

 " On the Winds, &c., of the North Atlantic, along the Tracks (and from 

 the logs) of North German Lloyd Steamers, between the Channel and 

 New York.'* 



* On page 103 (14), the question of force, as encountered by ships in motion, is alluded 

 to as not giving a correct estimate, as it ought to be the real amount without the efEect 

 of the ship's driving before it. The land observations also are modified by the above- 

 mentioned influence. A plan was proposed by Professor Piazzi Smyth, in conjunction 

 with Captain H. Toynbee, to nave the wind recorded from the mast-head, as the only part 

 of a ship not affected by the eddies from her sails ; the direction and force to be com- 

 municated electrically to the cabin and there recorded. See "Report of the British 

 Association," vol. xxv., page 45. 



t Translated from No. III. of the Mittheilungen aus der Norddeutschen Seewarte, 

 Ueber die Dampferwege zwischen dem Kanal und New York, nach den Journal-Ausziigen 

 der Dampfer des Norddeutschen Lloyd, in den Jahren 1860-67. Nebst Wind und Wettei 

 in derselben Zeit. Von W. von Freeden, Direktor. 



