384 •' Dr. blag den's Bj/lory of 
«. t ' * ^ • 
feems to be the only inftance that occurred of the freezing of 
quickfilver. F rom this circumffance, and his occafional hints 
about the climate, I am inclined to fufpedt, that the cold was 
not fo great in Siberia at this period, as when Dr. gmelin 
was therefrom 1734 to 1742. In Europe, likewife, the win- 
ters in general appear to have been feverer about the time of 
gmelin’s expedition than lately. It was in this very town of 
Krafnoyarlk that Pro fed or gmelin redded during the famous 
hard winter of 1739 and 1740; but unfortunately he has in- 
formed 11s of the cold there only by its grofler effects, I be- 
lieve becaufe his thermometers had been accidentally de- 
ft royed. 
§ 7. Nearly 500 miles fouth-eaftward of Krainoyarfk is 
the town of Irkutfk, the capital of a Siberian Province on 
the vaft Baikal Lake, and fituated in lat. 52. 0 N. and about the 
104th degree of E. longitude. At the former of thefe places, the 
cold recorded by Dr. pallas began to abate on the 7th of De- 
cember in the evening; and more than a day after, that is, on the 
9th in the morning, it became fo intenfe at Irkutfk as to freeze 
quickfilver. An account of this phenomenon, fent by Lieu- 
tenant-general von brill, the governor, was puhlifhed by 
Dr. pallas in his Journal*, and M. georgi, one of the aflo- 
ciates in this expedition, afterwards collected lome further par- 
ticulars f. It appears, that about four in the morning, the 
quickfilver was found frozen in the barometer and thermo- 
meter, its upper furface being irregularly broken. In the for- 
mer of thefe inftruments the mercury flood at 28 inches 7 lines, 
and the broken appearance extended through a fpace of about 
* Ibid. p. 419. 
4 Benaerlcungen einer Reife im Ruffifchefl Reich, B. I. p, 29. 
5 lines 
