GENERAL RE TORT. 29 



The fact here is apparent that between 33-34° it is actually lower 

 than between 40-41°. Even though this be but a single isolated fact, the 

 evidence that there has been some crudeness of observation would be 

 further confirmed by the fact that the same table shows between latitudes 

 37-38° it reaches so low as 10,625 feet. One probable source of error in 

 the above table appears from some observations kindly furnished me by 

 Mr. Francis Klett. Thus, on Meadow Mountain (California), timber-line 

 on the northern side was 11,200 feet, and on the southern, 12,000 feet. A 

 difference of 800 feet, actually observed (on a mountain isolated from any 

 great radiating surface, and one of a knot of peaks) between northern and 

 southern slopes, should lead to more specific statements as to the circum- 

 stances under which observations are taken. 



However, eliminating such exceptional cases as Sierra Blanca, Colorado, 

 10,410 feet, on the one hand, and La Plata Mountain, Colorado, 12,080 

 feet on the other, we may fairly infer these remaining thirty peaks were 

 evenly enough divided as to the exposure, etc., to give us an approximation 

 to the truth, and it would then even confirm Dr. Engelmann's statement that 

 there is little or no increase of altitude in timber-line toward the equator, 

 in our western hemisphere, south of the 41st parallel of north latitude. 



As to the agricultural prospects of Arizona and New Mexico, we may 

 safely venture on two assertions : first, that in neither of these Territories 

 have we reached anything like the real possibilities of the soil and climate ; 

 second, that in both of them there will always (so long, at least, as the 

 present climate endures) be an enormous percentage of waste land so far as 

 raising crops are concerned ; of this, much may be made available for 

 grazing purposes, and the remainder will, from its want of water, always 

 be worthless. 



The Valley of the Rio Grande, from Loma, in Colorado, south, may be 

 regarded as one continuous agricultural area, unpromising in appearance, 

 but rich in the elements of vegetable life. Throughout its entire length, 

 the cereals may be produced, and south of Santa Fe such fruits as grapes 

 and apricots yield an abundant crop. The ordinary garden vegetables do 

 well. This is, however, a mere strip, for the adjacent hills are at once 

 assigned to the division of sage-brush deserts. Like the Valley of the Nile, 



