VOL. LXXIII.] PHILOSOPHICAL TRANSACTIONS. 445 



town of Siberia, situated in 5Q±° n. lat. and 57° e. of Greenwich. On this oc- 

 casion he takes notice, that the thermometer had sunk there the preceding winter 

 to — 124°; which, if the general stile of the Abbe's remarks will allow suffi- 

 cient dependance to be placed on it, would necessarily show that the quicksilver 

 was then frozen. 



M. Erich Laxmann, late professor of mineralogy and chemistry at Petersburg, 

 was resident in 1765 at Barnaul in Siberia, lat. 53° n. and long. 81° e. as minister 

 to the German congregation of the Kolyvan province. On the first day of that 

 year, he saw the thermometer down so low as — 58°; whence it is probable, 

 that some part at least of the quicksilver was congealed. 



The benefits accruing from the travels of learned men could not escape the 

 penetration of the wise Empress Catharine. Soon after her establishment on the 

 throne, she ordered an expedition of the same nature as that in which Gmelin 

 had been engaged above 30 years before. Among the gentlemen who under- 

 took this 2d philosophical survey of the Russian empire, was Dr. Peter Simon 

 Pallas. The journal of his travels is published by himself in the German lan- 

 guage, and comprehends a rich store of curious and useful information. In ge- 

 neral his winters were not spent in the coldest parts of Asia; twice however he 

 resided at Krasnoyarsk lat. 56-i- n. long. 93° e. and the last time, in 1772, had 

 an opportunity of witnessing the most remarkable instance of the congelation of 

 mercury by natural cold that is vet known to the world. " The winter," says 

 M. Pallas, " set in early this year, and was felt in December with uncommon 

 severity. On the 6th and 7th of that month happened the greatest cold I have 

 ever experienced in Siberia; the air was calm at the time, and seemingly thick- 

 ened, so that, though the sky was in other respects clear, the sun appeared as 

 through a fog. I had only one small thermometer left, on which the scale went 

 no lower than — 70°; and on the 6th in the morning I remarked that the quick- 

 silver in it sunk into the ball, except some small columns which became solid and 

 stuck fast in the tube. By the temperature of a room not much warmed, into 

 which I brought the thermometer from the gallery of my house, these congealed 

 columns immediately fell down; but it was more than half a minute before the 

 mercury came into motion out of the ball. I repeated this experiment frequently, 

 and always with similar success, sometimes one and sometimes more threads of 

 frozen quicksilver remaining behind in the tube. When the ball of the ther- 

 mometer, as it hung in the open air, was warmed by being touched with the 

 fingers, the quicksilver rose; and it could plainly be seen, that the solid frozen 

 columns stuck and resisted a good while, and were at length pushed up with a 

 sort of violence. In the mean time I placed on the gallery on the north side of 

 my house about a quarter of a pound of clean and dry quicksilver in an open 

 bowl; within an hour I found the edges and surface of it frozen solid, and some 



