





8 feet Ther. 
Actual, 
By formula, 

Difference, 

6 feet Ther. 
Actual, 
By formula, 


| Difference, 

} 12 feet Ther. 
Actual, 
| By formula, 


| Difference, 


24 feet Ther. 
| Actual, 
| By formula, 
| Difference, 



OBSERVATIONS OF UNDERGROUND TEMPERATURE. 
Jan. 
—5-70|— 6-63 |— 5-96 
— 5:78 |— 6-54 |— 5-94 
+ -08 
— 2:98 
+ -02 
— 0-08 
—0-05 
08 
Feb. 

— -09 
— 2:96 |— 4:20 
— 4:20 

00 


—1:10 
—1:12 
+ -02 


+ 59/4 -45/4+ -21\/— -10/— -389/— - 

Mar. | April. 
— 3°82 
— 3°84 

+ -02 
—3-76 
—3-77 
°03/+ -0l 

— 2°24 
— 2:23 
— 1-86 
—1-89 
+ 03 ‘01 



May. June. 
— 0-40 
— 0°42 
+3°59 
+ 3:50 

+ -02 
—1-90 
—1:93 

+ -03 
— 2-04 
— 2-03 

— -:01 
| | | ee f | 


July. 
+ 6°43 
+ 6:58 
15 



+ 3°16 
+3°22 


06 

— 0:08 
—0O11 

au (03) 

— 63 
— 63 





































Aug. Sept. Dec 
+7:55|+ 6-48 — 3°65 
+ 7-60 |+6:20/+ 3-04 |—0-64 |— 3-76 
— -05/+ -28)— -16|— -11/+4 °:11 
+4-76|+4-99 | + 3-56 |4+ 1:26 |—1:07 
+ 4-82 |+4-91)+4 3-53 |+ 1-30 }—1:05 
— 06/+ -08/+ -03|— -04/— -02 
+1:15)+ 2-04} + 2°35 |4+ 2°10/4 1:02 
+1:14/+ 2:08 }+2°39 |}+4+ 2:00 /}+ 1:08 
+ -O1)— -04/— :04/4 :10/— -06 





— 49|— -21/+ °13)+ °43 
— 49)— -21/4+ +13)+ °43 






+ ‘61 
+ °60 
If we had neglected the term involving P, (the half-yearly term), and taken 
only the term involving P, (the annual term), we should have obtained the 
results entered in the first line of the following table. 
The numbers in the 
_ second line are the corrections necessary for reducing these results to the actual 








temperatures. 
Jan. Feb. 
Results, — 6:18 
Corrections, |+ ‘48 
Results, —3:10|—4°51 
Corrections, |+ :14/+ °31 
Results, +0:03|—1:13 
Corrections, |— -11/+ -03 
Results, + *62 
Corrections, |— -03|/— -02 





— 7:07 |—6:07 |— 3:44 
+ 44/4 -1l1)/— °38 



Je 
+ ‘01 






May. | June. 
+0°11)+ 3°63 
“b1/— -04 





—4-71|}— 3°65 |— 1-61 | + 0°86 
+ ‘16)— -11l}— :29|— ‘18 
—1-:98 |—2°31 |—2°02|—1-18 
+ 12/+ -07|— :02/— :11 






July. 


eel Sept. Oct. 
+7:07|+ 6:07 |+3:44)—0:11 
+ -48/+ -41/— -56/— -64 


+ 4°71/4+3°65)41-61 
+ ‘28/— -09|— -35 
+ 4:51 
+ -25 




+1:13 
+ 02 
+1:99 
+ 05 
42-31 | +4 2-02 
+ 04/4 -08 




‘47/— 21 
02 00 





+ -01}+ -02 






— 0°86 
21 

+1:18 
— ‘16 

+ 02 

