342 CHARLES DARWIN 



the sky an intense blue; the profound valleys; the wild 

 broken forms; the heaps of ruins, piled up during the lapse 

 of ages ; the bright-coloured rocks, contrasted with the quiet 

 mountains of snow; all these together produced a scene no 

 one could have imagined. Neither plant nor bird, excepting 

 a few condors wheeling around the higher pinnacles, dis- 

 tracted my attention from the inanimate mass. I felt glad 

 that I was alone: it was like watching a thunderstorm, or 

 hearing in full orchestra a chorus of the Messiah. 



On several patches of the snow I found the Protococcus 

 nivalis, or red snow, so well known from the accounts of 

 Arctic navigators. My attention was called to it, by observ- 

 ing the footsteps of the mules stained a pale red, as if their 

 hoofs had been slightly bloody. I at first thought that it was 

 owing to dust blown from the surrounding mountains of red 

 porphyry; for from the magnifying power of the crystals 

 of snow, the groups of these microscopical plants appeared 

 like coarse particles. The snow was coloured only where it 

 had thawed very rapidly, or had been accidentally crushed. 

 A little rubbed on paper gave it a faint rose tinge mingled 

 with a little brick-red. I afterwards scraped some off the 

 paper, and found that it consisted of groups of little spheres 

 in colourless cases, each of the thousandth part of an inch in 

 diameter. 



The wind on the crest of the Peuquenes, as just remarked, 

 is generally impetuous and very cold: it is said* to blow 

 steadily from the westward or Pacific side. As the observa- 

 tions have been chiefly made in summer, this wind must be 

 an upper and return current. The Peak of Teneriffe, with 

 a less elevation, and situated in lat. 28, in like manner falls 

 within an upper return stream. At first it appears rather 

 surprising, that the trade-wind along the northern parts of 

 Chile and on the coast of Peru, should blow in so very south- 

 erly a direction as it does ; but when we reflect that the Cor- 

 dillera, running in a north and south line, intercepts, like a 

 great wall, the entire depth of the lower atmospheric current, 

 we can easily see that the trade-wind must be drawn north- 

 ward, following the line of mountains, towards the equatorial 



* Dr. Gillies in Jpurn. of Nat. and Geograph. Science, Aug., 1830. This 

 author gives the heights of the Passes. 



