380 Transactions. — Chemistry and Physics. 



(12.) That the primary cause of winds is the difference of 

 temperature between the poles and the equator ; but the 

 interchange of the cold and heated air is not effected in one 

 great circulation on each side of the equator, but in a series 

 of upward and downward and round-and-round movements, 

 somewhat as shown in pi. lv., vol. xxxi., of the "Transac- 

 tions of the New Zealand Institute." By such complicated 

 motions the heat of the tropics and the cold at the poles are 

 modified, rain is scattered over the earth, and the air is 

 moved, mixed, and kept pure and healthy. We may not be 

 able to account clearly for the reasons of all these motions, 

 but the rotation of the earth and its globular shape account 

 for the directions of the circulations of cyclones and anti- 

 cyclones in the two hemispheres, and also for their eastward 

 progress, and for the greater activity of the belt of cyclones 

 in latitude 55° S. than of the anticyclones in latitude 30°, 

 because they are- nearer the pole, and they therefore feel 

 more strongly the difference between the rates of eastward 

 motion of the greater mass of air coming from the equator 

 and the smaller and slower-going mass coining from the 

 pole. All is evidently according to law ; yet, as in all other 

 branches of our knowledge, we observe constant variety in 

 the action, owing to varying interactions of the various forces 

 which cause it. What these forces are ultimately we are 

 unable to say, except that they are manifestations of the will 

 a,nd power of God. 



Art. XLVII. — Note on the Fog in Wellington on the Morning 



of the 19th June, 1900. 



By H. N. McLeod. 



[Read before the Wellington Philosophical Society, 28th August, 1900.} 



At 8 a.m., on looking northward from the vicinity of Fort 

 Gordon, near the entrance to Wellington Harbour, there 

 appeared to be a dense fog in the Hutt Valley, which stretched 

 thence along the line of railway into town in a comparatively 

 narrow bank. The fog did not extend as far as Soames 

 Island, and the slight breeze from the north carried the bank 

 into Wellington, where it became mingled with the smoke of 

 the city. The whole of Miramar Peninsula was quite clear 

 and sunny ; and I am informed that the same was the case 

 at Karori, and that at Wadestown there was but little fog. 

 From the Worser Bay hill, where the road crosses the saddle, 



