TO ROSETTA. 283 
spaces with the same substance. The mud soon chap. 
became dry, and very hard ; thus preserving . ^^' . 
the jars from the danger of being broken by 
any shock which the cases containing them 
might sustain ; and also, by the total exclusion 
of atmospheric air, preventing any change from 
taking place in the chemical constituents of the 
water. In this state they were sent, one to the 
University of Cambridge, and another to Pro- 
fessor Jacquin at Vienna. It is not yet known 
what chemical union takes place in Nile water, 
when the addition of pounded almonds causes it 
to precipitate the substances it holds in a state 
of imperfect solution : this is the common mode 
adopted in Egypt for clarifying the water. The chemical 
only result we have been able to obtain, of'Thr'^ 
from the most careful chemical analysis of the m^IToTiL 
Nile water, proves it to contain the carbonates of ^"'"" 
Magnesia, Lime, and Iron; the Muriat of Soda ; 
and a small portion of Silex and jilumine. But 
it is one of the purest waters known ; remark- 
able for its easy digestion by the stomach, and 
for its salutary qualities in all the uses to which 
it is applied'. The mud, or slime, left by this 
(1) " L'eau du Nil jouit d'une grand puret^ : cette qualitt^ la rend 
bien pr^cieuse, non seulement pour la preparation des alimens, mais 
encore pous les arts chymiques ou elle peut remplacer l'eau de pluie 
dont ce pays est priv^, et l'eau distill^e." La Decade Egyptienne, 
torn. I. p. 266. /^M Kaire, An 7. 
