Chap. 46.] 
VARIOFS KINDS Or KITBUM. 
513 
it is found, but in smaller quantities, and deteriorated with 
earthy substances, being known there as agrion."^ As to 
that prepared from the burnt wood of the quercus,^^ it never 
was made to any very great extent, and the manufacture of it 
has been long since totally abandoned. Mtrous^^ waters are also 
found in numerous places, but not sufficiently impregnated to 
admit of condensation.^^ 
The best and most abundant supply is found at Litee, in 
Macedonia, where it is known as Chalastricum it is white 
and pure, and closely resembles salt. In the middle of a cer- 
tain nitrous lake there, a spring of fresh water issues forth. In 
this lake the nitrum'^ forms for nine days, about the rising of 
the Dog-star, and then ceases for the same period, after which 
it again floats upon the surface, and then again ceases : facts 
which abundantly prove that it is the peculiar nature of the soil 
which generates the nitrum, it being very evident that, when 
the formation is there interrupted, neither the heat of the sun 
nor the fall of rain is productive of the slightest effect. It 
is also a truly marvellous fact, that though the spring of fresh 
water is always uninterruptedly flowing, the waters of the lake 
never increase or overflow. If it happens to rain on the days 
during which the nitrum is forming, the result is, that it is 
rendered additionally salt thereby : the prevalence of north- 
east winds, too, still more deteriorates its quality, as they have 
a tendency to stir up the mud at the bottom. Such is the 
formation of native nitrum. 
In Egypt, again, it is made artificially, and in much greater 
abundance, but of inferior quality, being tawny and full of 
6s Wild." 
See c. 40 of this Book. He is evidently speaking of a vegetable al- 
kali here. See Beckmann, Vol. II. pp. 492-3, Bohn's Ed. 
6^ Beckmann thinks that these kinds of water were in reality only im- 
pure and not potable, from their nauseous taste, and that hence they were 
considered as nitrous. Nitrous water, he remarks, or water containing 
saltpetre, in all probabiUty, does not exist. Vol. II. pp. 498-9. Bohn's 
Edition. 
^9 Or in other words, crystallization. Beckmann remarks that, in re- 
ference to alkaline water, this is undoubtedly true. Vol. II. p. 499. 
"'^ From the adjacent town of Chalastra, on the Thermaean Gulf. The 
site is probably occupied by the modern Kulakia. 
"'^ Carbonate of soda is found in the mineral waters of Seltzer and 
Carlsbad, and in the volcanic springs of Iceland, the Geysers more parti- 
cularly. 
VOL. V. L L 
