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barometrical measurement the highest of its 

 summits to be 4088m. (2097 toises) above the 

 level of the sea, which exceeds by 400 metres 

 that of the peak of Teneriffe. I sketched the 

 mountain from the vicinity of the great town of 

 Perote, in the arid plain covered with pumice 

 stone, which we crossed in ascending from Vera 

 Cruz to Mexico. The summit of the Coffer is a 

 naked rock, surrounded by a forest of pines. 

 On climbing this summit, I remarked, that the 

 oaks disappeared at the height of 3165 metres 

 (1619 toises) ; but the pines, which in their 

 leaves resemble the pinus strobus, are seen at the 

 height of 3942 metres (2202 toises). Under 

 each zone, the temperature and barometric pres- 

 sure prescribe to the vegetable world the limits, 

 which it cannot pass. 



