After returning from Canada, Pehr Kalm has written twice to Linnaeus, from New York [this letter has not come down to us] and from Philadelphia [this letter]. In accordance with the wish of the Royal Swedish Academy of Sciences [Kungliga Svenska Vetenskapsakademien], he will stay another year in America, until the autumn of 1750. This expedition will be costly because of the high exchange rate. Travelling is also more complicated in America than in Sweden and Russia. In the woods the grass is shoulder-high, trees are intertwined by thorny smilax so you must sometimes crawl on the ground. In the trees green, very venomous, snakes are hidden that can bite you in the face and kill you. On the ground there are rattlesnakes. Often you cannot hear their warning rattle because of the shrill sounds of all the cicadas and crickets. Kalm mentions two, especially critical, events: the night when they were in distress at sea, and last summer when they were almost caught by murderous Indians in the wilderness; on that occasion they were rescued by a group of French people, otherwise they would have starved to death. Here you can make thousands of observations, but the terrible heat makes work difficult in summer. Many get sunstroke and die, others die after drinking ice-cold water too greedily. Winter is extremely cold. Kalm’s Celsius [Anders Celsius] thermometer showed 24 degrees below zero in January compared to the Fahrenheit [Daniel Gabriel Fahrenheit’s] scale, where the mercury fell so low that it was not possible to calculate.
In summer you can see millions of fireflies; then it looks as if the forests are all ablaze. This is a species of Cantharis. There are oxfrogs that sound like bellowing oxen. There is a species of doves, so numerous that they fill the whole sky. There are locusts, woodlice, and many, many other animals Kalm would love to tell Linnaeus of, but a ship is soon leaving so he must finish here. He sends his regards to Sten Carl Bielke and all his benefactors and friends. He has no time to write to Bielke, his mother [Catharina Kalm] or to others.