92 
original notice of this peculiarity, in a reprint of that 
paper which has lately appeared ( £ Familiar Lectures on 
Scientific Subjects/ p. 144, note), an analogy is suggested 
between the fact in question and the transverse rotation of 
the etherial molecules in the propagation of a circularly 
polarized ray of light. 
“The remarkable feature in question as it now appears 
from this statement of Monsr. Buys Ballot, is no special 
peculiarity of the November gales, but a general one. And 
as such, an origin has to be sought for it in the dynamical 
laws which connect the movements of the individual aerial 
particles (which constitutes the wind) with the direction 
and progress of the advancing form which constitutes the 
atmospheric wave. 
“Weber, in his ‘Wellenlehre/ has made us familiar with the 
conception of the propagation of a wave by the successive 
transfer from particle to particle of circular or elliptic move- 
ments. In the case of undulating liquids — to which his 
work chiefly refers, the plane of such circulation coincides 
with the line of advance of the wave, and thus are easily 
explained all the phenomena of breakers and (as I have 
since shown) of alternating tide currents. But there is 
nothing, dynamically speaking, to limit such circulating 
movements to that plane. It is equally conceivable that 
their plane may be obliquely situated: and that a wave 
may be propagated even in the extreme case of the perpen- 
dicularity of the two directions, the phoenomena of polarized 
light alluded to, demonstrate. I cannot help thinking 
then that a general feature of this nature being now so 
strikingly brought before us, there is something more than 
a mere resemblance in the phoenomena I have thus ventured 
to assimilate and that the attention of hydrodynamicians 
might be advantageously directed to the subject as likely 
to cast some additional light on the mechanism of storms. 
“ P.S. — Would it not be worth while to enquire whether 
