Peter Simon Pallas arrived in Irkutsk an hour before midnight on March 14, 1772. He was accompanied by a painter and three naturalists. The horses, he writes, we tired. It was a week before the equinox but the rivers were still frozen and there was plenty of snow on the ground in that part of the world. This was a feature, not a bug, as far as travel in Siberia was concerned. When the temperatures rose, the whole country would become one endless, roadless, mosquito-filled bog. Since the beginning of the Russian state, the fastest way to travel its vast expanses had been by sleigh in the winter. He could have used those frozen rivers and snowy ground to continue deeper into Siberia but Irkutsk was his goal. He wrote that he knew the city held curiosities he had to see and stories he had to hear about the unknown land across Lake Baikal. Irkutsk did not disappoint. The governor had a rhinoceros to show him.
Pallas had arrived in Russian four years earlier at the invitation of Catherine the Great. He had been offered a teaching position at the Academy University, but that title was more a description of his pay grade and social status than a job description. He immediately set to work preparing for a five year expedition into the eastern provinces of Catherine's empire. Before leaving, he took time to look through the Academy's collections where he discovered a rhino skull that had been discovered near the Amur River on the Chinese-Siberian border. Numerous bones of rhinos along with hippos, elephants, and other tropical animals had been found in his native Germany and other parts of Europe. He wrote a paper describing this skull, tying it to the problem of the Siberian mammoth. Like most thinkers of his time, he was inclined to explain their presence in the north as a result of the Biblical flood washing the bones of tropical animals north. Pallas did not follow the usual method of scientific explorers, which was to collect samples and take notes and then analyze and write about them on their return. He sent several scientific papers back to the Academy and two volumes of a travel narrative while still on the road.
When Governor de Brill told him that he had preserved parts of an unknown large animal, Pallas' first thought was probably of a mammoth. Westerners knew of tales of bloody preserved mammoth carcasses as long as they had known about the mammoth. Earlier in the century there had even been a report by a reputable European. In addition, Pallas had seen dozens, possibly hundreds, of mammoth bones since leaving St. Petersburg. In his Travels, he wrote that there was hardly a river east of the Don that did not produce a few. He must have been both surprised and delighted when de Brill produced the head and feet of a rhino. During his four years on the road, Pallas had begun to doubt the wisdom of his having come to Russia. Captain Cook was the superstar of exploratory science. It seemed to Pallas that the South Seas was the real frontier. In Siberia, he lamented, one could go a hundred miles without discovering anything. A preserved rhino was something to get excited about.
Pallas was exceptionally lucky that almost everyone involved in bringing the mammoth to his attention had understood its importance. The rhino had been discovered by a group of Yakut (Sakha) hunters in December on the banks of the Vilui River, a tributary that fell into the Lena well above the Arctic Circle. The rhino was nearly complete when they found it, but enough of it was in a bad state of decay that decided to cut the feet and head from the carcass and leave the rest behind. In any case, even if they had wanted bring the whole body, breaking it loose from the frozen ground would have been almost impossible during the winter. The hunters took these parts to Ivan Argunov, the district magistrate who took a notarized statement detailing the location and position of the carcass and sent the parts and statement to the regional capital on Yakutsk in January. The authorities there kept one foot and sent the rest on to Irkutsk, where it arrived in late February, just three weeks before Pallas' arrival.
The head and feet were in excellent condition. Almost all of the skin was present and covered with hair. The delicate structure of the eyelids remained. Muscles and fat were preserved under the skin. Though the horns were missing, from the spots where they had been attached, he could tell it had been a two horned rhino. Of immediate concern was making sure it remained preserved in the best condition possible. It had already begun to give off a stench that he compared to "an ancient latrine." He chose to dry it in an oven. The melting fat falling in the fire caused the oven to get much hotter than he wanted and one of the feet was burned beyond any hope of saving. Naturally, the loss was blamed on an inattentive servant although I feel confident in say that no one in Irkutsk had any experience in drying rhinoceros parts so we should cut him some slack. Pallas took careful measurements of the head and feet and wrote a detailed article (in Latin) for the Academy. He would have liked to have spent more time studying it, but the Siberian Spring was coming and he wanted to get across Lake Baikal before the ice broke.
The Vilui rhinoceros as it appeared with Pallas' description (source)
Pallas' paper was published in the Academy yearbook for 1772 and eagerly read by scholars all over Europe. When he returned in 1774 he was covered in honors and eagerly sought out by other scientists. Moving to Russia turned not to have been a bad choice after all. he stayed in Russia for the rest of his working life. His rhino did not disappear into the Academy collections never to be seen again. During the Nineteenth Century, other scientists continued to study it. Its blood was examined, the remains of its last meal were picked out of its teeth, and, in 1849, Johann Friedrich von Brandt, the head of the zoology division at the Academy wrote a book length anatomical study of the remains. As an introduction to his study, Brandt went over the documents relating to the discovery.
In his rush to leave Irkutsk, Pallas regretted not having had time to make drawings of the remains. The Academy made up for this lack by having an artist prepare a detailed set of drawings of the head in profile and the remaining foot from the front and side. When Brandt made his study, he had an artist make new drawings, though not as detailed, of the head from all angles. By Brandt's time, enough other remains, especially horns had been made that they were beginning to be able reconstruct the Siberian rhino and see how different it was from living rhinos. One detail that particularly stood out was how unusual the horns were. Instead of being essentially conical, like those of living rhinos, The horns they were finding in Siberia were flat as a knife blade and ridiculously long, sometimes three or even four feet. Brandt had his artist match the skull up with one of the horns in their collection to give readers an idea of the horn's magnitude.
The Vilui rhinoceros as it appeared with Brandt's description. Because color printing was still rare, the illustration was most likely had colored. In either case, the use of color demonstrates the importance the Academy placed on the study. (source)
Like many extinct animals, the name of Siberian rhino has gone through many permutations over the years, from Rhinocerotis antiquitatis to Gryphus antiquitatus to Rhinocerotis tichorhini to its current name Coelodonta antiquitatis. It's commonly called the woolly rhino and is one of the best known ice age animals after the mammoth and sabre toothed tiger. Pallas never did have his name attached to it. It's curious that he didn't give it a name. At the time, he was working on his own naming system to fix the weaknesses that he saw in the Linnaean system. As it was, the naming credit has gone to Johann Friedrich Blumenbach who, coincidentally, also named the mammoth. Pallas needn't feel slighted; he named and has had named after him a number of other species.