Chap. III. PLAYA OF GKANADA. 35 
lute publicity. I have observed, as a general rule at this 
public place, that young and beautiful women were more 
modest than others who were not in possession of sufficient 
charms to attract the eyes of men, and in some cases of 
shocking ugliness no reason for modesty at all seemed to 
exist in the opinion of those most immediately concerned 
in the question. This observation, which contradicts a 
remark made by Goethe, is not without its moral interest. 
It is merely justice to add that, however slightly the com- 
mon people of Nicaragua may think of chastity and 
external modesty, I have never witnessed any coarseness 
or vulgarity of behaviour in the promiscuous crowd of this 
public bathing-place of both sexes. 
During the season of the trade-winds a heavy surf is 
generally breaking over the beach, and I have often heard 
its roaring in my bedroom in the centre of the city. By 
the action of the waves on the sand a separation of its con- 
stituent parts, according to their specific gravity, is effected, 
and by this process whole banks of black sand, composed of 
grains of titanic iron, or iserine, have been formed at some 
places, mixed only with a few grains of olivine, spinell, 
ryakolite, and other minerals of volcanic origin. These sub- 
stances are derived from the different masses ejected from 
the crater of the Mombacho, either in the form of lava or in 
that of ashes, which have made, or contributed to make, 
the volcanic tuff of this region. Everywhere in the neigh- 
bourhood blocks of lava are found imbedded in this tuff. 
The lava is sometimes of a basaltic character, including 
particles of titanic iron, of spinell, and of trichromatic 
olivine (red, blue, green, according to the three axes) — 
sometimes it is of a trachytic nature, including various mi- 
nerals of the felspar family, such as ryakolite and others. 
The basaltic lava not seldom takes the form of a very 
d 2 
