occurred at Lima, but
there was no trembling of the earth. According to the old chronicle
writers, the earthquake of 1630 was more disastrous.

The serious commotions which take place on the Peruvian coast appear to
acquire progressively greater extension, but only in the southern and
northern directions. A shock, of which Lima is the centre, though felt
fifty leagues towards the north, and as far towards the south, may,
nevertheless, be imperceptible in the easterly direction (towards the
mountains) at the distance of ten or twelve leagues. This peculiarity is
made manifest, not only by the terraqueous oscillations, but also by the
undulations of the sound, which usually proceeds still further in a
direction towards the south or the north.

Slight shocks are usually only local, and are not felt beyond the limits
of a few square miles.

The atmospheric phenomena during and after earthquakes are very
different. In general, the atmosphere is tranquil, but occasionally a
stormy agitation is the harbinger of a change. I was unexpectedly
overtaken by a violent commotion on the sand-flat between Chancay and
Lima. The whole surface of the plain presented a kind of curling
movement, and on every side small columns of sand rose, and whirled
round and round. The mules stopped of their own accord, and spread out
their legs as for support and to secure themselves against
apprehended danger. The _arieros_ (mule-drivers) leaped from their
saddles, threw themselves on their knees beside the animals, and
prayed to heaven for mercy.

The effect of earthquakes on the fertility of the soil is sometimes
remarkable. Numerous observations tend to show that after violent
commotions luxuriant lands often become barren wastes, and for several
years produce no thriving vegetation. Several Quebradas in the province
of Truxillo, formerly remarkable for their fertility in grain, were left
fallow for twenty years after the earthquake of 1630, as the soil would
produce nothing. Similar cases occurred at Supe, Huaura, Lima, and Yca.
All kinds of grain appear to be very susceptible to the changes produced
by earthquakes. Cases are recorded in which, after slight shocks, fields
of maize in full bloom have withered; and in the course of a day or two
the crops have perished.

The causes of the frequent earthquakes on the coast of Lima are
involved in an obscurity too deep to be unveiled. That they are
connected with volcanic phenomena seems probabl