ve been removed from the shore by
important elevations of the coast, are to be found only on hills.

During the first year of the deposit the strata are white, and the guano
is then called _Guano Blanco_. In the opinion of the Peruvian
cultivators, this is the most efficacious kind. It is found in the Punta
de Hormillos, on the islands of Islay, Jesus, Margarita, &c.

As soon as the dealers in guano begin to work one of the beds, the
island on which it is formed, is abandoned by the birds. It has also
been remarked, that since the increase of trade and navigation, they
have withdrawn from the islands in the neighborhood of the ports.

Much has recently been written on the employment and utility of guano;
but the manner in which it is applied as manure in Peru, seems to be but
little known. The Peruvians use it chiefly in the cultivation of maize
and potatoes. A few weeks after the seeds begin to shoot, a little
hollow is dug round each root, and is filled up with guano, which is
afterwards covered with a layer of earth. After the lapse of twelve or
fifteen hours, the whole field is laid under water, and is left in that
state for some hours. Of the _Guano Blanco_ a less quantity suffices,
and the field must be more speedily and abundantly watered, otherwise
the roots would be destroyed. The effect of this manure is incredibly
rapid. In a few days the growth of a plant is doubled. If the manure be
repeated a second time, but in smaller quantity, a rich harvest is
certain. At least, the produce will be threefold that which would have
been obtained from the unmanured soil.

The haciendas of the valley of Chancay have, during the last fifty
years, consumed annually from 33,000 to 36,000 bushels of guano brought
from the islands of Chancha and Pisco. The price of the bushel of
colored guano is one dollar and a quarter, and the price of the white
from two to three dollars. The price has recently undergone many
fluctuations, in consequence of the great exports to Europe.

The employment of this kind of manure is very ancient in Peru; and there
is authentic evidence of its having been used in the time of the Incas.
The white guano was then chiefly found on the islands opposite to
Chincha; so that for upwards of 600 years the deposit has been
progressively removed from those islands without any apparent decrease
of the accumulation. The uniformity of climate on a coast where there is
not much rain, must contribute to render t