1866.] 



267 



[ChnFe. 



(riij) i" calculating the last two of the above ratios, they approxi- 

 mate more nearly to the other four (31.04 X jij 4- lio = 24 ; 

 33.8-23 Xrk-^ Tiff = 26.17). 



The final ratios of the table show that the thermomctric intersolsti- 

 tial range bears nearly the same proportion to the daily land range, as 

 the annual range of temperature bears to the temperature-variation 

 which corresponds to the annual barometric range. 



The observations at St. Bernard show a remarkable tabular corres- 

 pondence, both in the parallelism between the daily temperature- 

 variations and the cosines of the hour-angles (Table I), and in the 

 approximation of the daily thermometrie range (Table II) to the 

 mean of the land and maritime ranges (Table V). The general 

 average of Table I, viz. : 



0° 15° 30° 45° 60° 75° 



1. .972 .888 .745 .548 .286 



exhibits the greatest difference from the cosine ratios at the hour- 

 angle of 75°, when the observed excess is rf^^ or 10.4 per cent. 

 The greatest local difference (^-^|^^ := 40.92 per cent.) is shown 

 at Toronto, at the same hour-angle. 



Many physicists have supposed that heat and attraction are but 

 opposite phases of a single force, and the hydrodynamic researches 



Table III. — Average North American Annual Eange. 



Av. Bar. Range 180° 



Av. Bar. Height ^ .367 



101°.5.^25°.217 



= 25°.217 

 4.024 



