38 OIL-FIELD WATERS IN SAN JOAQUIN VALLEY, CAL. 
line earths (Ca and Mg), and the common acids as strong acids (Cl, 
S0 4 , and N0 3 ) and weak acids (C0 3 , HC0 3 , and S). The reactive 
properties of a water are governed by the respective proportions of 
these groups. Thus, if the value of the alkalies exceeds that of the 
strong acids, the hardness of the water may be removed simply by 
boiling, but if the strong acids exceed the alkalies, the water is per¬ 
manently hard. Similarly, if the value of the strong acids is less 
than that of the alkalies plus the earths, the water is characterized 
by alkalinity, but if it is greater the water is acid. 
In order to define more exactly the properties of a water, Palmer 
considers in detail the balances that may exist between the two basic 
and two acid groups of radicles and assigns to each a name. Salinity 
is defined as the property induced by the strong acids and alkalinity 
as that measured by the weak acids. The properties due to the 
presence of alkalies are called primary, and those due to the presence 
of the alkaline earths secondary properties. Hence the balance 
between the alkalies and the strong acids is called primary salinity 
and that between the alkaline earths and the weak acids secondary 
alkalinity, which is more commonly known as temporary hardness. 
If the strong acids exceed the alkalies, the excess must be held in 
equilibrium by the alkaline earths, and this balance is accordingly 
called secondary salinity, which is permanent hardness. If, on the 
other hand, the alkalies exceed the strong acids, the excess is bal¬ 
anced against the weak acids, and this balance is known as primary 
alkalinity. The two last-named properties are obviously incompati¬ 
ble ; nearly all waters are characterized by either one or the other, 
but a water can not exhibit both. All the oil-field waters are char¬ 
acterized by primary salinity and secondary alkalinity and by either 
primary alkalinity or secondary salinity. The three properties fur¬ 
nish a rational basis for classification and preliminary study, and are 
evidently far more convenient for general comparison than the de¬ 
tailed analyses. 
The manner in which these properties are deduced from the analysis 
is shown graphically in figure 2, which represents analysis 31 (Table 5, 
p. 66). It is assumed that the analysis has already been converted 
into the ionic form and that the reacting values of the radicles have 
been determined and reduced to a percentage basis as previously 
described. In this form the values of the basic radicles constitute 
50 per cent of the total and those of the acid radicles 50 per cent. 
In the figure the bases and acids have been plotted to scale in two 
columns of equal length, the alkalies and strong acids being placed 
at the bottom and the earths and weak acids above. In the central 
column are shown the properties of reaction that result from the 
proportions of these groups shown. As primary salinity is due 
to the balance between equal values of the alkalies and strong acids 
