NOTES ON PARICEJTIN VOLCANO 
W. F. Foshag 
May 21, 1943 
Arrived at Paricutin. The cone has grown considerably since I saw it in 
March with Ing. Ordonez and appears to be more active. Present height 350 m. 
Fumarolic activity in the old flow has diminished, probably due to dampening 
by the ash that has fallen upon them. The lava is no longer flowing. 
Some rain. 
May 22. 
Went along the north and east edge of flow. In the swale, below 
Dr. Atl's house, where fumaroles were so abundant in March, there are now 
scarcely any. Crossed over the top of the old flow, examining fumaroles along 
the western edge of the old flow. There are not as many here as along the 
eastern front. In the pinnacles that project above the cover of ash, are 
orange and yellow salts, and the fumaroles have a strong smell of hydrochloric 
acid. Heached the base of the cone, where there were numerous bomb craters, 
seme of them still hot. Followed along the west front of the flow where I 
found an area of ash covered by a thin white efflorescence of salts, presumably 
ammonium chloride and other salts dissolved from the ash by yesterday’s rain. 
Set up a funnel and a tube in a small fumarole near the northwestern front 
near the crest of the old flow. Water immediately condensed in the tube. 
Three hours later a crust of salts had formed in both the tube and the funnel. 
At 5:30, began to rain heavily and the front of the lava began to show much 
steam, with a little from the summits of the two peaks on the lava flow, but 
none on the top of the lava. The heavy rain came from the west and the 
western slope of the cone became covered with clouds of steam that rose up 
the slope and were sucked over the crater rim. 
Good night display, but not equal to yesterday's. 
May 23. 
Went to the funnel and tube. The tube was crusted with a white sublimate 
in fine needles and botryoidal masses. The upper part carried some condensed 
water having a slight saline taste. The funnel carried a crust of white salts 
with streaks of pale yellow. There appeared to be some condensation in the 
water-bottle, with which the funnel was connected and the contained water had 
a slight saline taste. 
Later went to the east side of the flow to study some fumaroles but some 
boipbs fell close by, dropping with a swishing noise. One that fell nearby, 
having a diameter of about 10 inches had a surface temperature of 202°C. 
Began to rain, so returned to the casita. 
Observed a long streak of steam down the side of the cone, reaching almost 
to the bottom, as if a small stream of water had run down, and later another 
smaller one. 
At 6 PM, very hazy, with later dense steams olouds from the fumaroles 
drifting to the east and filling the basin, with fog. 
During the night heavy falls of large blocks from the crater many of which 
came quite far out, accompanied by heavy drumming of falling rocks. 
May 24. 
Fine clear day, spent mostly in photography. In an old dead pine tree 
near the lava flow found two squirrels, apparently contented. Later a blue 
jay came and fought with one of the squirrels. Caught insects upon the ash, 
many leaf-hoppers, some spiders, a large grasshopper, a longicornis and others, 
oaw one sulfur butterfly and later a large bright one. Also saw large lizard 
scamper between the b^locks of the old lava. In the afternoon took colored 
pictures of some of the fumaroles. 
The volcano was magnificent at night. 
