Synthesized answer
Humboldt's work advanced scientific investigation by collecting and publishing materials that aimed to "throw some light on the history of nations, and advance the study of nature" [2]. He focused on physical geography, an area he considered most important, seeking to understand the geographical relations of the vegetable world and the limits of plant height on mountains [1, 2]. His expeditions contributed to the "vegetable riches of the Old World" and brought new knowledge to Europe [3].
Specifically, Humboldt and M. Bonpland's discoveries included a complete picture of the botany of the equinoctial regions of America and other visited places, with observations that had escaped previous travelers [3]. They collected geological specimens from significant locations like Chimborazo and the Amazon River, which had not previously been brought to Europe [4]. Humboldt's efforts also aimed to fill gaps in scientific knowledge regarding mountain heights, atmospheric phenomena, and magnetic forces, areas where he felt existing maritime expeditions were less effective than inland travels [5].
Synthesized from the book passages below. Chat with the book on Feynman for follow-up.
From the book
the World, Theory of the Earth, or Physical Geography. The last of these two objects seemed to me the most important. I was passionately devoted to botany and certain parts of zoology, and I flattered myself that our investigations might add some new species to those already known, both in the animal and vegetable kingdoms; but preferring the connection of facts which have been long observed, to the knowledge of insulated facts, although new, the discovery of an unknown genus seemed to me far less interesting than an observation on the geographical relations of the vegetable world,…
he zeal and equanimity of that friend never failed, amidst the fatigues and dangers to which we were sometimes exposed. Under these favourable circumstances, traversing regions which for ages have remained almost unknown to most of the nations of Europe, I might add even to Spain, M. Bonpland and myself collected a considerable number of materials, the publication of which may throw some light on the history of nations, and advance the study of nature. I had in view a two-fold purpose in the travels of which I now publish the historical narrative. I wished to make known the countries…
ascended the Andes, contributed by their discoveries and collections to augment the vegetable riches of the Old World. But, in their time, geology as a science had little or no existence. Of the structure of the giant mountains of our globe scarcely anything was understood; whilst nothing was known beneath the earth in the New World, except what related to her mines of gold and silver. It remained for Humboldt to supply all that was wanting, by the publication of his Personal Narrative. In this, more than in any other of his works, he shows his power of contemplating nature in all…
their relations with each other, and the eternal ties which link the phenomena of life, and those of inanimate nature. Having stated the general object I had in view in my expeditions, I will now hasten to give a slight sketch of the whole of the collections and observations which we have accumulated, and the union of which is the aim and end of every scientific journey. The maritime war, during our abode in America, having rendered communication with Europe very uncertain, we found ourselves compelled, in order to diminish the chance of losses, to form three different collections.…
ce, particularly geology, the history of the modifications of the atmosphere, and the physiology of animals and plants. I saw with regret, (and all scientific men have shared this feeling) that whilst the number of accurate instruments was daily increasing, we were still ignorant of the height of many mountains and elevated plains; of the periodical oscillations of the aerial ocean; of the limit of perpetual snow within the polar circle and on the borders of the torrid zone; of the variable intensity of the magnetic forces, and of many other phenomena equally important. Maritime…