x i v INTRODUCTION. 



of the water 67'3; the mean standing of the barometer 29-784 in., 

 and the mean degree of moisture -798. The winds were variable, 

 generally light, from the east or seaward ; with these the barometer 

 rose, while those from the southwest depressed it. The range of the 

 photometer was from 20 to 93 during fine weather and a clear sky. 

 A thermometer placed three feet below the surface for several hours 

 showed 75-5; another placed in the sand rose to 114 y and continued 

 so from 9 A. M. till noon ; one covered with wool, a foot above the soil, 

 stood at 90, while an uncovered one similarly situated showed 82'3. 

 During these trials the degree of moisture was '854, the wind moderate 

 from the northeast, and the sky quite clear. The temperature of a cave, 

 inclined about thirty-five degrees to the horizon, and twelve feet deep, 

 with south exposure, situated in a bluff of soft gray sandstone, having 

 a perfectly horizontal stratification, was 70 Fahr. : although this 

 affords but an approximate result for the mean temperature, yet it 

 indicates a very high mean annual temperature for the latitude. 

 That such is the case seems very probable from the accounts derived 

 from the most intelligent of the inhabitants at the Rio Negro on the 

 east, and San Carlos de Chiloe on the west, lying nearly in the same 

 latitude, and which are the most southern points where settlements 

 have been formed : at both places snow and ice are seldom seen ; they 

 experience no severe cold ; but frosts are frequent during the winter 

 months, from May to October, when gales of wind are experienced 

 from the southward and eastward. 



The great peculiarity of the climate of Patagonia is its dryness. 

 The pampas are destitute of verdure, and unfitted for the abode of 

 civilized man, except in a few localities where the rivers which flow 

 from the interior enable cultivation to be carried on by irrigation. 

 The situation of the southern part of South America, which includes 

 Patagonia and New Chili, is peculiar, occupying a strip of continent 

 only three hundred miles in breadth, lying between the two great 

 oceans, the coasts of both sides trending nearly north and south, a lofty 

 range of the Andes extending throughout its entire length and covering 

 one-fifth of its width ; with the wide and barren pampas on the east, 

 and the narrow and luxuriant forests on the west, rising even to the 

 limits of eternal snow ; the former enjoying a clear and cloudless sky 

 and a dry and temperate atmosphere, while the latter is subject to vio- 

 lent gales of wind from the westward, accompanied by heavy rains, 

 producing a redundancy of moisture and almost constant cloudy 

 weather, yet with a like temperate climate. The cause of these 



