n of the country which is
best appreciated by a consideration of the works which were published in
consequence of that immense accumulation of materials gathered during
those explorations. From Lima, or rather from Callao, he sails in 1802
for Guayaquil and Acapulco, and reaches Mexico in 1803, where he makes
as extensive explorations as he had made in Venezuela and the Andes, and
after a stay of about a year, and having put all his collections and
manuscripts in order, revisits Cuba for a short time, comes to the
United States, makes a hurried excursion to Philadelphia and Washington,
where he is welcomed by Jefferson, and finally returns with his faithful
companion Bonpland to France, accompanied by a young Spanish nobleman,
Don Carlo de Montufar, who had shared his travels since his visits to
Quito.

At thirty-six years of age Humboldt is again in Europe with collections
made in foreign lands, such as had never been brought together before.
But here we meet with a singular circumstance. The German nobleman, the
friend of the Prussian and Spanish courts, chooses Paris for his
residence, and remains there twenty-two years to work out the result of
his scientific labor; for since his return, with the exception of short
journeys to Italy, England and Germany, sometimes accompanying the King
of Prussia, sometimes alone, or accompanied by scientific friends, he is
entirely occupied in scientific labors and studies. So passes the time
to the year 1827, and no doubt he was induced to make this choice of a
residence by the extraordinary concourse of distinguished men in all
branches of science with whom he thought he could best discuss the
results of his own observations. I shall presently have something to say
about the works he completed during that most laborious period of his
life. I will only add now, that in 1827 he returned to Berlin
permanently, having been urged of late by the King of Prussia again and
again to return to his native land. And there he delivered a series of
lectures preparatory to the publication of "Cosmos;" for in substance,
even in form and arrangement, these lectures, of which the papers of the
day gave short accounts, are a sort of prologue to the "Cosmos," and a
preparation for its publication. In 1829, when he was sixty years of
age, he undertakes another great journey. He accepts the invitation of
the Emperor Nicholas to visit the Ural Mountains, with a view of
examining the gold mines, and loc