Single blocks of Stone. 375 
hydrogen loses much of its odour, and the alcohol, when 
water is added to it, becomes milky, and in a close vessel 
it deposites, in the course of a few hours, an odoriferous 
volatile oil, which was contained in the gas, and which 
gave it its well known smell. pigs Berzelius. 
9. When Hydrogen gas is substituted for azotic gas in 
the mixture which constitutes atmospheric air, and this 
mixture is respired by men or other animals, it very soon 
throws them into a profound sleep, without appearing to 
have any injurious effect, especially if a little common air 
is admitted to the mixture ; but if in this composition of 
air carbonated hydrogen is substituted for azote, the mix- 
ture when respired is highly deleterious. Idem. 
10. Whena few drops of fuming nitric acid are let fali 
into a flask of sulphuretted hydrogen, the hydrogen becomes 
oxidized at the expense of the nitric acid and forms water, 
while the disengaged sulphur appears in the solid form. 
If the flask be closed with the finger, so that the gas, which 
becomes warm, Cannot escape, the heat increases suffi- 
ciently to cause the gas to burn with a beautiful flame, and 
slight detonations are preduced which repel the finger 
from the orifice of the flask. This experiment may be 
made without the least danger, with a flask whose contents 
are 4 or 5 cubic inches. — Idme. 
11. Single blocks of Stone. ‘Tne enormous columns of 
granite, destined for the portico of the new church now 
building in the place d’Isaac at St. Petersburg, are very 
remarkable. In order to form a proper estimate of their 
size, we will here state the comparative magnitudes of the 
largest blocks known, both ancient and modern. Ist. The 
column of Alexandria commonly called Pompey’s pillar, 
which holds the first rank. It is of a single block of Red 
granite, in height 67 feet 4 inches 111 lines. 2d. The 
columns of the Church d’Isaac just mentioned, in height 
56 feet. 3d. The columns whose ruins are near mount 
Citorio at Rome, height 52 feet 4 inches. 4th. Columns 
of the portico of the Pantheon, height 46 feet 9 inches 11 
lines. 5th. Columns of the cathedral of Casan, at St. 
Petersburg, height 42 feet. 6th. Two columns of the 
