He begins his diary of August 1773 with O'Taheite:
It was one of those beautiful mornings which the poets of all nations have attempted to describe, when we saw the isle of O'Taheite within two miles before us. The east wind, which had carried us so far, was entirely vanished, and a faint breeze only wafted a delicious perfume from the land, and curled the surface of the sea. The mountains, clothed with forests, rose majestic in various spiry forms, on which we already perceived the light of the rising sun ... everything seemed as yet asleep; the morning scarce dawned, and a peaceful shade still rested on the landscape....
This spot was one of the most beautiful I had ever seen, and could not fail of bringing to remembrance the most fanciful descriptions of poets, which it eclipsed in beauty; we had a prospect of the plain below us, and of the sea beyond it. In the shade of trees, whose branches hung over the water, we enjoyed a pleasant gale, which softened the heat of the day; and, amidst the solemn uniform noise of the waterfall, which was but seldom interrupted by the whistling of birds, we sat down....
We could have been well pleased to have passed the whole day in this retirement ... however, feasting our eyes once more with the romantic scenery, we returned to the plain.
It was such descriptions as these which stimulated Humboldt. There is a breath of poetry in his writings; his Views of Nature and Cosmos give ample proof that love of Nature and knowledge of Nature can condition and deepen each other.
It is not surprising that in the flood of scientific 'Travels' which followed, especially in imitation of Forster, there were some that laid claim to a wonderful grade of feeling. For example, the description of a day at the Equator by von Spix and v. Martius in their Travels in Brazil in 1817 to 1820:
In these seas the sun rises from the ocean with great splendour, and gilds the clouds accumulated in the horizon, which in grand and various groups seem to present to the eye of the spectator continents with high mountains and valleys, with volcanoes and seas, mythological and other strange creations of fancy.
The lamp of day gradually rises in the transparent blue sky; the damp grey fogs subside; the sea is calm or gently rises and falls, with a surface smooth as a mirror, in a regular motion. At noon a pale, faintly shining cloud rises, the herald of a sudden tempest, which at once disturbs the tranquillity of the sea. Thunder and lightning seem as if they would split our planet; but a heavy rain of a salt taste, pouring down in the midst of roaring whirlwinds, puts an end to the raging of the elements, and several semi-circular rainbows, extended over the ocean like gay triumphal arches, announce the peaceful termination of the great natural phenomenon. As soon as the air and sea have recovered their equilibrium, the sky again shews its transparent azure.... As the sun gradually sinks in the clouded horizon, the sea and sky assume a new dress, which is beyond description sublime and magnificent. The most brilliant red, yellow, violet, in infinite shades and contrasts, are poured out in profusion over the azure of the firmament, and are reflected in still gayer variety from the surface of the water. The day departs amid continued lightning on the dusky horizon, while the moon in silent majesty rises from the unbounded ocean into the cloudless upper regions. Variable winds cool the atmosphere; numerous falling stars, coming particularly from the south, shed a magic light; the dark-blue firmament, reflected with the constellations on the untroubled bosom of the water, represents the image of the wholly starry hemisphere; and the ocean, agitated even by the faintest breeze of the night, is changed into a sea of waving fire.... The variety of the light and foliage of the trees, which is seen in the forests, on the slopes of the mountains: the blending of the most diverse colours, and the dark azure and transparency of the sky, impart to the landscapes of the tropical countries a charm to which even the pencil of a Salvator Rosa and a Claude cannot do justice....
Except at noon, when all living creatures in the torrid zone seek shade and repose, and when a solemn silence is diffused over the scene, illumined by the dazzling beams of the sun, every hour of the day calls into action another race of animals.... When the sun goes down, most of the animals retire to rest ... myriads of luminous beetles now begin to fly about like ignes fatui, and the blood-sucking bats hover like phantoms in the profound darkness of the night.... The traveller does not here meet with the impressions of those sublime and rugged high Alps of Europe, nor, on the other hand, those of a meaner nature; but the character of these landscapes combines grandeur with simplicity and softness....
He who has not personally experienced the enchantment of tranquil moonlight nights in these happy latitudes can never be inspired, even by the most faithful description, with those feelings which scenes of such wondrous beauty excite in the mind of the beholder.
A delicate transparent mist hangs over the country, the moon shines brightly amid heavy and singularly grouped clouds, the outlines of the objects illuminated by it are clear and well defined, while a magic twilight seems to remove from the eye those which are in shade. Scarce a breath of air is stirring, and the neighbouring mimosas, that have folded up their leaves to sleep, stand motionless beside the dark crowns of the manga, the jaca, and the ethereal jambos; or sometimes a sudden wind arises and the juiceless leaves of the acaju rustle, the richly flowered grumijama and pitanga let drop a fragrant shower of snow-white blossoms; the crowns of the majestic palms wave slowly over the silent roof which they overshade, like a symbol of peace and tranquillity.
Shrill cries of the cicada, the grasshopper, and tree frog make an incessant hum, and produce by their monotony a pleasing melancholy.... Every half-hour different balsamic odours fill the air, and other flowers alternately unfold their leaves to the night.... While the silent vegetable world, illuminated by scores of fireflies as by a thousand moving stars, charms the night by its delicate effluvia, brilliant lightnings play incessantly on the horizon, and elevate the mind in joyful admiration to the stars, which, glowing in solemn silence in the firmament above the continent and ocean, fill the soul with a presentiment of still sublimer wonders.
Travels by sea were described at much greater length and with much more effusion than travels by land; one might infer from the silence of the people who moved about in Europe in the eighteenth century, that no love of Nature existed. The extreme discomfort of the road up to a hundred years ago may account for this silence within Germany.
Lady Mary Wortley Montagu wrote in 1716 of Saxon Switzerland:
We passed by moonshine the frightful precipices that divide Bohemia from Saxony, at the bottom of which runs the river Elbe ... in many places the road is so narrow that I could not discern an inch of space between the wheels and the precipice....
and her husband declared that
he had passed the Alps five times in different places, without having gone a road so dangerous.