3 so A YEAR OF COSTA RICAN NATURAL HISTORY 



Three days later, on the afternoon of January twenty- 

 fifth, 1910, the country about Alajuela was thrown Into the 

 wildest excitement by the sight of Poas in violent eruption, 

 which began about 4.50 P. M. and lasted half an hour. 

 The volcano is some ten miles away and the cloud of steam 

 rose in puffs, spread out into mushroom shape, then, blown 

 by the high wind, traveled rapidly toward El Brazil. In 

 twenty minutes the cloud was directly overhead, looking by 

 that time like any ordinary cloud, and at intervals there was 

 a distinctly sulphurous smell. As it came puffing out of the 

 volcano the soft white steam looked extremely beautiful 

 in the afternoon sun against a perfectly blue sky. From 

 5.30 to 5.40 there was a second much less vigorous eruption, 

 the cloud from which remained over the volcano as long as 

 we watched it. No sounds were heard, nor was there any 

 fire or dark smoke from the volcano. 



About 6.15 began a fall of very fine but gritty ash, pale 

 gray in color, acid and biting in taste and reminding me 

 strongly of the " blitz pulver " we used in old flash-light days. 

 From microscopic examination later. Prof. A. P. Brown 

 pronounced it to be an enstatite andesite ash containing 

 glass. It fell like a damp mist and soon formed a well-defined 

 layer over everything — roofs, porch rails, coffee tarpaulins, 

 leaves of trees. The cloud of ash covered the whole sky 

 across the zenith. By nine o'clock the volcano was perfectly 

 clear and free from clouds and there seemed to be no further 

 precipitation of dust. The next morning the ash looked 

 like a fall of fine snow, just enough to whiten the ground 

 but not cover it. 



An eruption of Poas of this force and accompanied by such 

 quantities of ash was not common and the people were 

 badly frightened. The usual eruptions are geyser-like 

 spoutings of steam and mud. The native superstition is 

 that the eruptions are caused by treating the volcano with 



