ON THE PACIFIC COAST 325 
traveller who strays from these landmarks : he soon 
gets bewildered among the medanos or shifting 
hills of sand, and finds his grave in one of them. 
To see the sun setting over this desert is like look- 
ing into the red-hot mouth of a furnace, and there 
is usually a lull in the wind at that hour ; but he 
has barely disappeared when a rapid refrigeration 
sets in, the night-wind sweeps over the desert, and 
at daybreak the cold is as sensible (of course not 
so intense) as on the paramos of the Andes. 
Piura is one of the driest places in the world, 
and in "winter," as it is called (December to April), 
one of the hottest. Yet it is very healthy, catarrhal 
complaints, caused by the violent winds charged with 
sand, being the only prevalent ones. The site is 
a very curious one to have been chosen for a city. 
There is a river, it is true, but for six months in the 
year its bed is dry. It is now raining hard in the 
Andes, where its sources are, and some time next 
month the water is expected to reach Piura. 
March 27, 1863. — . . . We are just now passing 
through the hottest fit of weather I ever experi- 
enced. Fancy a minimum thermometer at 85°, 
which has usually been the lowest temperature in 
the twenty-four hours ever since the ist of March ; 
indeed, up to the present date, it has only three 
times been as low as It is true that through- 
out the same period the thermometer has never 
risen higher than 89° ; but such sustained and 
nearly uniform heat induces great languor. The 
hottest part of the year is considered to be almost 
past, and the months to come will get gradually 
cooler. Although Piura cannot be said to have a 
