90 OLD STREAM OF LAVA. Book I. 
suddenly concreted. It is narrow above and widening 
below, bordered all around with the trees of the forest, the 
contrast producing an effect not less striking than that of 
the trees growing on the side of a glacier, The points and 
edges of this mass of lava are so formidable, that the idea 
of making an excursion on it is given up with great damage 
to the shoes after the first experiment of a few steps. 
Some strange hollow cylinders or tubes, somewhat similar 
in appearance to huge hollow trunks of trees burnt to 
charcoal, but formed of the lava, have arrested the atten- 
tion of travellers, some of whom have conjectured that 
these masses were really produced by the lava surrounding 
trees. I have spoken of similar formations occurring on the 
sides of the volcano of Telica, and it is my opinion that 
they have been caused by portions of half-cooled lava rolled 
along on the surface of the stream, as in the case of Nindiri, 
or on the ground as in the case of Telica, while a develop- 
ment of gas was going on in their interior ; a process by 
which cylindrical balloons, opened afterwards in one way or 
the other, may have been formed, though by this explana- 
tion I do not pretend to deny the possibility of these tubes 
being casts formed round the trunks of trees, only the fact 
that hollow masses of lava exist in many other forms at the 
same localities has made me doubt it. 1 
I spent a night at Masaya, a considerable town with a 
very active Indian population in its suburbs. More luxu- 
riant plantain gardens, and finer fruit trees cannot be seen. 
All the fences are living hedges of piiiuela or wild pine- 
apple. On the market place, early in the morning, many 
interesting and highly creditable articles of Indian skill 
1 An eruption of the Volcano of Masaya has taken place since the time when I 
was in Nicaragua. 
