It follows from this that the amounts of two alkali bases required for the saturation of an acid must be in the same ratio for the saturation of another acid; in general, granted an alkali as unit, if the series of numerical ratios in which various acids saturate it is established, then this series is the same for any other alkali, except that the various alkalis are to be taken in different relative amounts and these amounts, for their part, again form an equally stable series of exponents for each of their opposite acids, for they stand to each in just the same ratio as to any other.