132 NOTES OF A NATURALIST. 



were before Mejillones, which lies fully thirty miles 

 north of the former place. It stands on a little bay, 

 well sheltered from the south by a considerable rocky 

 promontory, and, as I had been led to expect, the 

 ground is here broken and irregular, offering more 

 promise of safe retreat for the indigenous vegetation 

 than anywhere else on this coast. I had looked 

 forward with interest to an hour or two on this more 

 promising ground, and it was a disappointment to be 

 unable to profit by a comparatively long stay, for we 

 remained at anchor after nightfall, embarking cargo 

 and some passengers until midnight. For the third 

 time within twenty-four hours we crossed the Tropic 

 of Capricorn, and thenceforward remained in the 

 south temperate zone. But in this region the term is 

 in no way specially appropriate to the coast climate 

 of Chili, for nothing can be more truly temperate than 

 that of the so-called tropical zone which we were 

 now leaving. During the voyage from Callao the 

 thermometer properly shaded had but once (while 

 anchored at Arica) reached 70° Fahr. It usually stood 

 by night at 64" to 65°, and at about 68° by day, except 

 occasionally when exposed to the cool southern 

 breeze, when it fell rapidly on two occasions, marking 

 only 62'2°. 



My aneroid barometer by Casella, graduated only 

 to 19 inches, and therefore useless during my visit to 

 the Cordillera, did not appear to have suffered, as 

 these instruments often do, by the reduced pressure. 

 It did not vary during seven days by so much as 

 one-twentieth of an inch from the constant pressure 

 29.9, and agreed closely with the ship's mercurial 



