246 Intelligence and Miscellaneous Articles. 



estimate of the average monthly increase of solar altitude at all 

 places in the temperate zones : — 



Months from winter solstice. 1. 2. 3. 4. 5. 6. 



Increase of solar altitude ... 3° 12° 23^° 35° 43|° 47° 



Ratio of increase -0(59 -255 -500 745 -931 1-000 



If we allow about twenty- four days for the cumulative effects of 

 increasing heat and cold, these ratios become properly comparable 

 with the monthly ratios of temperature-variation, as in the follow- 

 ing Table, which is compiled from the works of Dove and Guyot : — 



Difference of time, months . . 1. 2. 3. 4. 5. 6. 



Ratios of sines -076 -284 -545 784 -946 1 



Ratios of arcs -069 -255 -500 745 -931 1 



Northern hemisphere -076 -259 -512 753 -935 1 



Southern hemisphere -077 '281 -538 763 -938 1 



Arctic region -071 -231 -479 733 -934 1 



Europe -069 -239 -501 738 -938 I 



Asia '097 -274 -535 769 -934 1 



North America ... -055 -279 -494 741 -917 1 



South America ... '077 -275 -501 724 -936 1 



Africa -088 -267 -537 761 -938 1 



Australia '081 -313 -618 -801 -913 1 



An extensive series of comparisons * seems to warrant the follow- 

 ing inferences, all of which are confirmed by other considerations : — 



(1) Taking into view the entire land surface of the globe and the 

 entire range of the year, the direct heat of the sun and the induced 

 aerial currents appear to be about equally instrumental in determi- 

 ning fluctuations of temperature. 



(2) The influence of the winds is most marked in the Northern 

 and Western hemispheres ; that of solar obliquity in the Southern 

 and Eastern hemispheres. 



(3) Where the sun's rays are least intense (as in the Polar Re- 

 gions) and where the winds are most variable, the ratios exhibit the 

 nearest parallelism to the increments of arc ; but where the winds are 

 most uniform (in and near the region of monsoons) they correspond 

 more closely with the sinal increments. 



(4) The general changes of temperature at midwinter and at 

 the equinoctial seasons (when the sun's declination is changing 

 most rapidly) are most dependent upon the local solar heat ; the 

 midsummer changes are more subject to the influence of the winds. 



(5) The greatest conflict of opposing forces occurs during the 

 sun's passage between the comparatively wind-governed Northern 

 hemisphere and the sun-governed Southern hemisphere. This con- 

 flict is manifested in the spring and autumn rains. 



(6) The closest and most general approximation of ratios is shown 

 in the monthly-temperature change at midsummer, which corre- 

 sponds almost precisely with the change of arc. — Silliman's American 

 Journal for July 1867. . 



ON THE SPONTANEOUS CHANGE OF A LIQUID CYLINDER INTO 

 ISOLATED SPHERES. BY DR. FELIX PLATEAU^. 



In the second series of his researches " On the Figures of Equili- 

 * See Proceedings, &c, loc. cit. 



t From a separate impression from the Bulletin de I' Academic Royale de 

 Bruxelles, No. 7, 1867- Communicated by the Author. 



