HEINRICH WILHELM DOVE. 389 



water, not obedient to the same law of direction, may originate in the 

 conflict of local and accidental winds. 



What Dove has called the " Law of Rotation " of the winds has a 

 more universal, though a less boisterous, applicability to the facts of 

 meteorology than his "Law of Storms." Aristotle appears to have 

 had glimpses of this law, according to which all changes of the wind, 

 not Local and transitory, followed each other, not at random, but in a 

 regular order, which is reversed for the southern hemisphere. This 

 law declares, in popular language, that there is no permanent change 

 of weather if the wind backs round. Bacon in 1G00, and Sturm in 

 1G76, refer to this rule ; farmers and navigators are familiar with it. 

 Bacon says : " Si ventus se mutet conformiter ad motum solis . . . non 

 revertitur plerumque, aut, si hoc facit, fit ad breve tempus." As was 

 said at Dove's Jubilee : " For two thousand years men had witnessed 

 the phenomenon without seizing the significance of it." Dove found 

 the explanation in the incessant struggle between the equatorial and 

 polar currents of the same hemisphere, which alternately push each 

 other up and down and from one meridian to another. His educated 

 ear caught in the whisperings or rustlings of the winds the key-note to 

 all the non-periodical changes of the weather ; and he elucidated his 

 views by the discussion of thousands of observations of the barome- 

 ter, thermometer, and hygrometer, extending over fifty years. If 

 Dove gave a wider extension and a more exclusive jurisdiction to 

 Iladley's theory of the trade-winds than all meteorologists would be 

 ready to admit, if he did not allow sufficient scope to the centripetal 

 theory and to antecedent influences which caused the two antagonistic 

 currents to dislodge one another, nevertheless he succeeded in bring- 

 ing order out of chaos, and in shedding the light of a principle on a 

 • confused mass of heterogeneous observations. Truly has it been 

 said : " By his Herculean but well-directed labor he has written his 

 name in large, imperishable characters on the records of science." 

 Dove first appeared before the world as an author in 1827. with a 

 paper on the Winds. This was followed by eight others, all of them 

 on meteorology, and the largest part of his voluminous writings were 

 on the same subject. His last publication in the Abhandlungen 

 of the Berlin Academy, was on the weather of 1875-76, and his 

 contribution to the Jubelband of Poggendorff was on the meteoro- 

 logical differences between the northern and southern hemispheres. 

 Par excellence, Dove was a meteorologist. 



Some of Dove's most valuable contributions to journals or trans- 

 actions were also published as independent works. His ' : Gcsetz der 



