4 Dr, Wollaston's Synoptic Scale 
with muriate of magnesia, it would appear to be 73 instead 
of 67,3. 
In recurring to the tables of Kir wan, a similar obstacle 
presents itself to the determination of the quantity of muriatic 
' acid, that is equivalent to a given weight of sulphuric acid. 
When the comparison is made by means of potash, the result 
would make it appear that 68,3 is the relative weight of mu- 
riatic acid. But, if the compounds of these acids with lime be 
employed in the computation, the result instead of 68,3 gives 
only 59. 
Richter remarked, on observing this sort of inconsistency, 
that if sulphate of potash formed according to the proportions 
of Kir WAN were decomposed by muriate of lime, there should 
be found a large excess of alkali in the solution. But, on the 
contrary, by direct experiment he found that neutral salts, 
when mixed, remained in all cases neutral, and consequently, 
that the same weight of muriatic acid would in all cases be 
found equivalent to the same quantity of sulphuric acid ; and 
therefore might be conveniently expressed in stating the 
composition of salts, by the same number. He estimates this 
acid at 712, as the equivalent to 1000 dry sulphuric acid, the 
number assumed as his standard of comparison, to which all 
other numbers for acids, alkalies, and earths are adapted. 
It could not escape the penetration of M. Berthollet, that 
there exist numerous deviations from this law of neutraliza- 
tion, and cases of prevailing affinity dependent on a redund- 
ance of one or other ingredient in a mixture of salts. But he 
was not so happy in detecting the definite law, by which many, 
at least, of these deviations are governed. It has since been 
found, that when a base unites with a larger portion of acid 
