114 



ROYAL SOCIETY OF CANADA 



Kange of 4" Thermometer Compared with Sunshine, Rainfall, 

 AND Air-temperature Range. 



Date. 

 1895. 



July 



Readings. 



Min. Time. Max. 



h.m. 

 700 



• 700 



700 



7-00 



700 



710 



700 



700 



7-30 



68-94 

 69-61 

 72-18 

 71-58 

 72 15 

 75-38 

 71-32 

 67-28 

 71-90 



Time. 



h.m. 

 18-30 



18 -10 



18-15 



18-20 



18-30 



18 30 



18-25 



17-25 



18-10 



R'nge 



4-85 

 4-50 

 5-76 

 1-44 

 3-94 

 4-55 

 6-67 

 1-66 

 5-53 



Hours 



of 

 Sun 

 Shine 



Rain- 

 fall 



Inches 



Air 



Th'rm 

 Range 



000 

 000 

 0-00 

 000 

 000 



Inapp, 

 00 

 0-13 



Inapp 



19-4 



17-2 

 23-1 

 11-2 

 15-5 



18-5 

 19-0 

 18-7 

 18 



Remarks 



Value of the Diffusivity from the Annual Range. 



Having now a set of observations extending over 18 months, we are 

 able to determine the annual range of temperature at the different 

 depths, and to deduce a general average value of the diffusivity by com- 

 paiing the ranges. 



It will be observed that except for the deepest thermometer, the 

 curves of temperature are of a very peculiar type, and are very far from 

 being simple harmonic. The curves were accordingly subjected to a 

 grai)hic method of analysis to deduce the range of the annual simple 

 liarnKjnic components lor each dej)th. The iollowing results were 

 obtained : — 



Taking the above results in pairs, we deduce from any two of them 

 the value k/c = 'OOSG for the diMusivity. The agreement of the differ- 



