258 



THE PLANT WORLD. 



western fjirc nf llic j-ock is a slicci' ])i'('<*i|)ic(' ot ufcal deplli. 

 When we threw stniies from the eiloc the souiid uf tlieir impact 

 reached us after an interval of feni- luxl u half or live seconds. 

 From the edge of this precipice we get a most magnificent view 

 of the surrounding country. Immediately at our feet is the 

 broad wash of the Cafiada del Oro, beyond lie the Tortolita 

 Mountains, whieli. though of fairly resjjectable size, can scarcely 

 be distinguishe<l un<ler tlie noonday sun as anything but irreg- 

 ularities in the <>('n(n-al surface. Off fifty miles to the south- 



Figure 52. On the top of Castle Rock. Live oak and pine on the left, 

 juniper and pinon pine on the right, Yucca and bear grass in centre, with 

 a century plant. Agave Palmeri, in the right foreground. The slender 

 flower stalk is that of the amole. 



west, beyond the Tucson ^fountains eighteen miles distant, avc 

 see the Baboquivari Alountains and the Coyotes; to the south 

 the Santa Eitas with their wonderful extent of foothill country 

 sloping off towards the west; and midway between, the 8ierri- 

 tas; to the northwest rise the Superstition Mountains, and to the 

 west, beyond the Maricopa, divide the Big Horns. The view 

 extends in a circle, except where it is interrupted by the Cata- 

 liiui range back of us, \vith a radius of 175 or 200 miles, and 



