10 LETTER FROM M. E. BOUEGEAU. 



Various Observations on Temperature made at Carlton in 1858. 



Measurement of some of the largest Trees observed in the 

 Neighbourhood of Carlton. 



Cirqumference in French metres. 



Metres. Centimetres. 



Populus balsamifera 2 53 



Populus tremuloides i 15 



Abies alba 2 25 



Observed by Lieut. Blakiston, at Mosquito Point, on the Lower Saskatchewan, 

 lat. 53** 50', long. 102° 53': — Abies alba? 2 metres, 58 centimetres. The largest 

 remarked, after quitting Hudson's Bay, near the great rapid of the Saskatchewan, 

 I m. 60 cent. 



Observed by myself in the Valley of Arches in the Rocky Mountains : — Abies 

 nigra? 3 m. 69 cent, nearly; height about 160 feet. Most of the forest-trees had 

 nothing remarkable in their size, the too frequent burning of the forests forming 

 an impediment to the development of their beauty. 



A few Observations on the Temperature of the Earth in the 

 Prairies of the Saskatchewan. 



