Johann Jakob Scheuchzer (1672-1733) was a Swiss physician, but also quite interested in travels and natural sciences. He published his observations on the culture and natural world of the Alps as "Itinera per Helvetiae alpinas regiones facta annis 1702-1711".
In the introduction by the editor we read:
"The name of Scheuchzer will be famous … The author was in the best conditions to make valid discoveries during his explorations. He worked with incredible determination..,  no danger, no costs, no difficulty were too large for this great man."
Despite the work was intended to dispel of myths and superstitions so common in the Alps, Scheuchzer, like many other naturalists of his time, did not see a contradiction in publishing own and exact observation and rumors in the same book. In the German translation of the "Itinera alpina" by Johann Georg Sulzer, published in 1746 with the title "Natur-Geschichte des Schweizerlandes" (Natural History of Swiss) so we read about dragons:
"In the summer of the year 1717 Joseph Gackerer from Neftls... a half hour distant from Glarus...… encountered an animal with the head of a cat, with large eyes, it was long a foot, with a thick body, four limbs, and something like breasts pending from the belly, the tail was a foot long, the entire body was covered by scales and colored. The man touched it with a stick; it was soft and full of poisoned blood, so that from some drops spilled on his leg, it became swollen.
I requested to mister Tschudi, pastor at the village of Schwanken, that he would find an honest person which would search for the bones of this person, so in April 1718 he send some to me, which I hold in my collection as rare specimens."
Fig.2-4. For centuries the inhabitants of remote valleys in the Alps were convinced that, hidden in the forests and caves, strange creatures existed, like serpents with a human face, lizards with multiple tails and the most fearsome of all - the terrible Tatzelwurm (all images in public domain).
Scheuchzer dedicates an entire chapter to encounters with these strange creatures.
"From the evil dragon must also be told……Years ago, an honest man named Mcyer …[recounts] … above the village of Ommen under the shade of a large fir tree was seen to lie [a dragon]. He had legs and wings, which were characterized by red spots, [the wings of the color] like silver.
The man turned back as soon as he had seen him. Two days afterwards there was a storm with hail, which confirms the common believe of the locals that severe storms occur after a dragon is spotted. This would not be without reason. Because we know that after the dilution of the air and before it rains creatures like snakes, lizards and similar animals tend to come out from their holes."
Scheuchzer however is sometimes skeptic about local legends and correctly notes in one case that bones attributed to dragons are more probably from known animals:
"...an observation of the year 1718, there in a cave on a very high mountain, called Ober-Urner-Schwendi, there were found some bones, declared as the remains of a dragon, but after my judgment these are nothing more than the remains of a bear, which maybe hibernated in the cave and because of the collapse of the entrance must have died there by starvation."
Scheuchzer also offers a geological explanation for the dragon myth:
"At last I must mention, that furious rivers from the mountains are called by the locals of the Alps also dragons. If a river flows down from the mountains, and carries large stone, trees and other things with it, so they say: The dragon became unchained...... that many false stories about the dragons have their source in this fact."
MÄGDEFRAU, K. (1973): Geschichte der Botanik. Stuttgart, Gustav Fischer.