THE CLIMATE. 91 



ing to those of spring and summer during the first two months, but through May as often 

 reversed as in winter. l>< tween the coldest and warmest hours of the day there is an average 

 difference of 20; and between the extreme heat of the first and the cold of the last month, the 

 tlicnm.itirtrr ranges through 50, though the difference of their mean temperature is only 10, 

 and that of the season 59. 4, differing very slightly from that of the whole year. The hygro- 

 metric condition of the atmosphere changes more rapidly : the mean height of a wet thermo- 

 in. t. r at ;{ p. M. during March being 16 below its temperature; and in May, at the same hour, 

 only 8. 5. The average difference at all the observation hours in the former month is 10. 1, 

 and in the latter 4. 3; even the very last figures proving that there is still a less amount of 

 aqueous vapor in the atmosphere than during the driest months at Washington. These would 

 tell the reader that the rainy season was not fully commenced, had he not been prepared for 

 the fact by the compilation from the tables of Seiior Reyes. Our three years give a somewhat 

 different result, showing an increase in the average daily time during which rain falls in May, 

 from 1h. 'Jm. to \h. 42m., and the deposit of water 6.9 inches. 



Every effort is made to harvest the crops of beans, capsicums, potatoes, and other vegetables, 

 for winter use, before the rains commence ; and as the grapes are ready for the vintage between 

 the 10th and 20th of April, this is the busiest season of the agriculturist. It is also the period of 

 the year when morning fogs are the most frequent; when the halos that almost nightly encircle 

 the moon are most opaque, and the meteors brightest ; when clouds above the Andes are in 

 densest masses, and storms of rain, snow, and lightning are phenomena of daily occurrence 

 among their heights. On one occasion a meteor exploded, in the direction of the greater Magel- 

 lanic cloud, with a noise so audible as to command attention ; and another, which was very 

 brilliant, was witnessed by Lieut. MacRae and myself, ascending from the S.E. quarter of the 

 heavens in a nearly vertical direction. 



More particularly during our last year, and in the months of May and June, there were 

 beams of light visible on many mornings, radiating from a point of the heavens opposite the 

 sun. Sometimes they were so broad, well defined, and distinct, as to give the intervening 

 shadows the appearance of black streamers on a rose-colored ground. The dark spaces were 

 usually blacker to the south than to the north of the zenith, across which many of them could 

 be traced almost to the eastern horizon. The effect was greatly heightened when there were 

 banks of cumuli about the mountains, for these were often brilliantly lighted up, as one wit- 

 nesses at a tropical sunset. Occasionally the phenomenon was visible on both sides at once ; 

 and then it was a most beautiful sight to watch one point of radiance descend as the other 

 gradually rose to the summit of the Andes. In twenty minutes to half an hour the presence of 

 the sun would obliterate every trace of it. 



Another phenomenon, which attracted my attention soon after reaching Chile, was the red 

 color assumed by the snow-crests as the sun approached the western horizon. The change of 

 color began as soon as the plain had fallen under the shadow of the Western Cordilleras, and 

 increased in depth until the direct light of the sun had entirely left the peaks. Above the 

 shadow of the Cordilleras, as it crept up the Andes, there were violet and purple hues, according 

 to their distance from the illuminated portion ; and not only these, but also the red, were of 

 greater intensity at the close of spring and in winter, when the sun was farthest north, and 

 there had been recent deposits from the clouds. At such times the view was certainly very 

 exquisite ; and if there were radiant beams of light and shade over the Andes at the same 

 time, as was quite frequently the case, it was a picture to which no words can render justice. 

 To my vision the color of the snow at such times was more of a vermillion than of a red or rose 

 color, but the assistants could only recognise it a rosy pink, even with prepared water-colors 

 before us ; another example that all eyes were never alike sensitive to colors. The Protococm 

 nivalis, mentioned by arctic voyagers, has been found also on patches of perpetual snow of 

 the Andes; but this shows the red color only when accidentally crushed, or a rapid thaw 



