Prof. Dove's Outlines of a general Theory of the Winds. $59 



( + ) signifies increase, ( — ) decrease. 



B. Hydrometeors — In three memoirs contained in these An- 

 nals (Poggendorff's) viz. " On the connection of hydrometeors 

 with the variations of the temperature and of the barometer," 

 (vol. xiii. p. 305), "On thunder-storms," (vol. xiii. p. 419), 

 and "Some remarks on rain," (vol. xxxi. p. 541), I have 

 specially proved that the atmospheric precipitates depending 

 on the direction of the wind, whether they appear as rain, 

 hail, or snow, whether accompanied with disengagements of 

 electricity or not, are nothing less than a necessary conse- 

 quence of the law of rotation. Since there is at present no 

 reason to modify the positions laid down in those papers, and 

 as these may rather be extended to the southern hemisphere, if 

 we consider the line drawn on it from SE. to NW. as a line of 

 division of the west and east side, a repetition in this place of 

 what has been stated in them, seems to me quite unnecessary. 



C. Currents which alternately expel each other. — In winter, 

 which is especially the time, when, on account of the greater 

 differences of temperature in the districts situated to the north 

 or south of the places of observation, all phenomena of weather 

 are for the greatest part occasioned by the wind, I have found 

 by comparison of the direction of the wind, as observed below, 

 with the passage of the higher clouds and the direction of the 

 finer fibres of the cirrus, that with SVV. and NE. winds the 

 under direction of the wind coincides with the passage of the 

 highest clouds; that on the contrary with W. and NW., with 

 E. and SE., the direction of the vane and of the lower cumu- 

 loid clouds is at right angles to the upper direction of the 

 wind. Besides this I have remarked, that when after a ba- 

 rometrical minimum with SW., the wind veers to the west, 

 and then goes round to north, dark mountainous cumulo- 

 strati advance from the western horizon immediately pre- 

 ceded by a cold wind, which raises the barometer, and which 

 in winter is combined with falls of snow, in spring with hail- 

 showers, and in summer with thunder-storms. This phseno- 



