Transits, Travels and Tribulations, III
In St. Petersburg he learned that, in light of his delays, the Russian Academy had given up hope of his reaching Tobolsk in time and had sent out expeditions of their own (which seem never to have been heard from) to nearer sites. But Chappe was determined to reach Tobolsk before the transit. Thanks to the Empress, his expedition was equipped with every necessity, from bread to interpreters, and left St. Petersburg in early March on four enclosed sleds, each drawn by five horses running abreast. (One pictures a scene out of Doctor Zhivago or something from Tolstoy.) The sleds were smashed beyond repair by the time they reached Moscow, but on March 17 they left that city with new sleds, still with nearly 800 leagues (3,800 kilometers) to go, including crossing the Urals. Paradoxically, while they cursed the bitter cold they prayed for continued cold weather. A thaw would strand them in the Siberian bogs, from which they might never emerge. It took a month (Chappe furiously writing reports on everything he encountered), even though "the surface of the Volga was as smooth as glass … and the sledges went on with inconceivable swiftness." His retinue chose to desert him in the depths of a Siberian forest, and Chappe had to hunt them down, pistol in hand, but eventually the expedition found itself in Tobolsk in mid-April, well before the June transit.
Aided by a military party appointed by the local Governor, Chappe soon built a working observatory on a nearby mountain, and began observations to determine his longitude and latitude, essential for the eventual calculations of Venus's distance. However, Tobolsk lies at the confluence of the Irtysh and Tobol rivers, and the thaw that set in with his arrival was unusually rapid, with heavy flooding of the town. To some locals, this was no doubt due to the activities of the foreigner said to be messing with the sun, and mutterings of mob action to deal with him necessitated an increase in Chappe's military guard.
Chappe could sleep only fitfully the night before the transit, even though he reported that "the perfect stillness of the universe completed my satisfaction and added to the serenity of my mind." The day itself proved perfect, and Chappe observed the entire transit. At the start, he says, "I was seized with an universal shivering." But as the hours wore on and success became ever more imminent, "I truly enjoyed [the pleasure of] my observation, and was delighted with the hopes of its being still useful to posterity, when I had quitted this life." Indeed his observations were still prominent in calculating the scale of the solar system more than 100 years later.
Couriers bearing the essential observational data were quickly dispatched to Paris and St. Petersburg, but Chappe himself stayed on making further latitude and longitude observations, not to mention notes on everything that came his way. He eventually made a leisurely return trip through southern Russia, arriving back in Paris almost 18 months after the transit. The only sour note came later when Chappe published his no doubt honest yet excoriating views on Russian backwardness, despite the help he had received from Russians throughout his travels. No less a personage than Catherine II, writing under a pseudonym, undertook a line-by-line rebuttal. No matter. For the next transit Chappe was to abandon the winter wastelands of Russia for the deserts of Mexico.