' the Dead Sea and the River Jordan. 301 
which, from a number of experiments performed with great 
care by Mr. Tennant and myself, appeared to be 56,1 parts of 
lime in 100 of marble. From a great variety of trials, made 
with considerable attention, and with due allowance for any 
accidental circumstances, muriat of lime appeared to consist of 
5°, 77 parts of lime, to 49,23 of muriatic acid. 
2. To ascertain the proportions of earth and acid in muriat 
of magnesia, required a synthetic process somewhat different. 
To a known weight of pure magnesia perfectly calcined, a 
known quantity of acid* was added, and after the whole of 
the magnesia was dissolved, the remaining portion of acid was 
saturated by marble. From the loss sustained by the marble, 
and the known proportions of acid and magnesia used, the 
composition of muriat of magnesia (supposed perfectly free 
from water) was deduced, and the proportions resulting from 
several careful trials, were 43,99 parts of magnesia, to 56,01 
of muriatic acid. 
3. Muriat of soda was analysed by various methods. But 
the only one which I shall now relate consisted in precipitating 
the acid by a solution of silver from a known weight of muriat 
of soda, and inferring the proportion of acid and alkali from 
the quantity of luna cornea obtained. This however required a 
previous exact knowledge of the proportions of acid and silver 
in luna cornea. In order to ascertain this point, a known quan- 
tity of acid was precipitated by nitrat of silver, and the weight 
* By a known quantity of acid, is meant as much acid as will dissolve a known 
weight of marble. In all these experiments the quantities of acid were not weighed, 
but measured by means of a peculiar apparatus, and the real weights or intrinsic 
quantities of acid, corresponding to the measures in question, were easily deduced 
from the results above mentioned. 
MDCCCVII. 
R r 
