46 OP CLOUDS. CHAP. 2. 1. 



these pointing fibres; how comes the cirrus 

 itself, though apparently stationary, to be 

 actually moving on slowly in an opposite 

 direction? which I have observed to be the 

 case ; and, indeed, cirri in general move along 

 with their tails either foremost or aslant. If 

 these cirri, then, be moved along by the current 

 of air, it cannot be imagined that there can be 

 a current of differently electrified air meeting 

 them, which should draw out their tails into 

 transmitting points. For if two currents meet, 

 which ever was strongest would counteract the 

 other, and would move the cirrus at the rate of 

 the difference of the two velocities. It is diffi- 

 cult, too, to suppose that there can be a tide 

 of electricity moving against the wind; but it 

 is possible that the cirrus may not be carried 

 forward by the mechanical impulse of wind. 

 The same electric attraction, which may draw 

 out its cirriform tail, for the purpose of equali- 

 zation, may, be supposed, furthermore, to move 

 slowly the whole mass in the same direction. 

 I never could quite satisfy myself on this point. 

 Perhaps the electric attraction, which draws out 

 the cirrus into transmitting points, exercises 

 its power quite independent of the wind then 

 blowing; for these cirri sometimes move in a 



