“The statement given below of the duration of sunlight in the months of May, June, July and August, serves to show that a difference in latitude has not the same effect in changing the summer temperatures of places in high latitudes as it has in more southerly localities. Unfortunately, the records at posts in the district are too few and meagre to either confirm or disprove this theory, and to use the records of such places as Fort Franklin, on Great Bear lake, and Fort Rae, on Great Slave lake, is hardly fair. These points are over three hundred miles apart in an air line, and the temperature at either or both may be influenced by the local conformation of the ground, or other unknown causes. However, taking the records at these places, we have the following comparison:— Mean temperature Fort Franklin, Fort Rae, during lat. 65° 12′ lat. 62° 40′ May, 35.2° Fahr. 27.7° Fahr. June, 51.4° 51.4° July, 52° 61.2° August, 50.6° 56.5° “The Fort Franklin data are given in Professor Loomis’s Meteorology, published in 1875. He gives as his authority Dove’s tables in the report of the British Association for 1847. Who the observer was is not stated, but it was probably Franklin. The Fort Rae statistics were furnished by Mr. Carpmael to the Senate committee appointed to inquire into the resources of Mackenzie basin, and cover the same months as those given for Fort Franklin. These statistics, as far as they go, confirm the theory, for the extremes at Fort Franklin differ 16.8°, while at Fort Rae the difference is 33.5°, and the monthly differences at the former place are much less than the latter.[18] “I have computed the following table which shows comprehensively the different durations of sunlight for the latitudes of Ottawa, Chipewyan, and Forts Simpson, Good Hope and McPherson. Ottawa. Chipewyan. Simpson. Good Hope. McPherson. Latitude 45° 26′ 58° 43′ 61° 52′ 66° 16′ 67° 26′ H. Sun. H. M. H. M. H. M. H. M. H. M. May 1: 14 08 15 34 16 05 17 06 17 30 June 1: 15 16 17 36 18 39 21 04 24 00 June 21: 15 30 18 44 19 14 22 48 24 00 July 1: 15 24 18 36 19 02 22 04 24 00 Aug. 1: 14 32 16 16 16 56 18 16 19 24 Aug. 31: 13 08 13 52 14 08 14 36 14 44