106 REPORT—1840. 
establish, but in stating briefly what I understand to be his 
fundamental positions, I shall at least have a better chance of 
rendering myself understood, than if I confined myself to the 
easier task of translating passages from the original works. 
204. Considering first the simple phenomenon of the dzrec- 
tion of the wind, apart from all others, it appears for ages to 
have been a belief that when the wind changes it does so ina 
constant direction, which is that of the hands of a watch, 
which for brevity we will call a Right-handed Rotation. 
M. Dove contrasts, not unaptly, the two following passages, 
one from Bacon, in the commencement of the 17th century, 
the other from a French physical writer of the 19th. The 
former says, ‘“‘Si ventus se mutet conformiter ad motum solis, 
non revertitur plerumque aut si hoc facit fit ad breve tempus ;” 
the latter, “On a cru remarquer que dans certains lieux les vents 
se succedent dans un ordre déterminé; mais ces observations 
présentent encore trop d’incertitudes pour qu’il nous soit per- 
mis de les discuter ici’’. The clear evidence which Dove pro- 
duces of the opinion of observers of various countries during a 
space of two hundred years, that the more freyuent and more per- 
manentrotations ofthe windare right-handed (in this hemisphere), 
give much support to his theory*. It is important to add, that 
the phenomena of the trade winds and monsoons enter as part 
of the expression of his general law of rotation (das Drehungs- 
gezets des Windes). 
205. It is very remarkable, from its connexion with a different 
inquiry presently to be noticed, that in the Southern Hemisphere 
the Law of Rotation is inverted, the movement of direction is 
Left-handed. In the Northern Hemisphere the order of winds is 
Peed Vite. Ning Bes 
In the Southern Hemisphere, 
sca Nag WY oy ots 
Of these circuits, the quadrants from S. to W. and N. to E. 
in the Northern Hemisphere, and from N. to W. and S. to E. 
in the Southern Hemisphere, are oftener traversed in an inverted 
order than the opposite quadrants}. 
206. This, however, is only a small part of M. Dove’s investi- 
gation, for he aims at showing that this law of succession thus 
determined, renders a certain order of meteorological pheno- 
mena of every kind indispensable, and he has laboured to assign 
* Meteorologische Untersuchungen, p. 132. Itisimportant to observe, that the 
direction of rotation here mentioned has no reference to the rotatory movement 
of the aerial particles themselves, which will be referred to in the next section. 
+ Meteorologische Untersuchungen, p. 129. It is to be observed, that this 
Law of Rotation especially applies to extra-tropical regions, where the mixture 
of equatorial and polar currents is most complete. 
