Secrion ITI., 1901 [13 ] Trans. R. S. C. 
IL.— Soil Temperatures. Observations with Electrical Resistance Ther- 
mometers at McGill College, Montreal. 
By Professor C. H. McLeop, Ma.E., of McGill University. 
(Read May 30, 1900.) 
The following summary of the observations of soil temperatures 
for the three years ending May 8th, 1900, is in continuation of the 
results already communicated to the Section by Professor Callendar and 
myself. An account of the apparatus employed and the method of re- 
duction will be found in the Transactions of the Society for 1895, 1896 
and 1897. 
The annual curves for the mean air temperature and for the tem- 
perature of the soil at the several depths at which the thermometers were 
buried, are presented for the three years in a form similar to the charts 
accompanying the earlier reports. 
The annual mean temperature for each year since the commence- 
ment of the observations is given below ; the year in each case beginning 
and ending with May 8th. 
ANNUAL MEAN TEMPERATURES AT THE SEVERAL DEPTHS TO WHICH THE THER- 
MOMETERS ARE BURIED. (The year extends from May 8 to May 8). 






Depth 1895-96 | 1896-97 | 1897-98 | 1898-99 | 1899-1900 | Average 
11 51°48 51°60 50°48 48°59 49°99 50°43 
4” 47°12 44°97 46°94 46°46 46°48 46°39 
10” 46°65 45°25 45°70 46°85 46°52 46°19 
20” 47°17 45°30 45°82 46°75 46°62 46°33 
40” 47°00 45°72 45°73 46°99 46°81 46°45 
66” 47°00 45°91 45°66 46°97 46 38 46°38 
108” 46°82 45°53 45°29 47°53 45°83 46°20 
PAVOLAZES .-."........... 47°61 46°33 46°52 47°16 46°95 46°91 
Air Temperatures .... .| 42°65 42°53 43°05 42°79 43 18 42°84 
Soil Temp. in excess of 

DITA ec puc es 4°96 3°80 3°47 4°37 3°77 4°07 

