of ionized acid›, and since the ions are the carriers of the current, the ‹conductivity› of the solution should be ‹increased› because of this change in the ‹composition› of the electrolyte. Experiment shows that such is the case. EXP. 20 c.c. of water is added to the 20 c.c. of 4-molar acid in the cell, and the mixture is stirred. The current is decidedly increased (from 0.17 to 0.22 ampere in the experiment under discussion). If 40, 80, 160 and 320 c.c. of water are added in succession to the contents of the cell, the conductivity is ‹increased by every addition of water›. But, while each addition dilutes the acid to one-half the previous concentration, the ‹increase grows proportionally smaller and smaller with increasing dilution›. In the following table, "Ratios I" are the ratios of the observed conductivities ‹to the original conductivity›, "Ratios II" the ratio of each observed conductivity to the ‹preceding one›. ‹Concentration› ‹Observed› Ratios I. Ratios II. ‹of Acid.› ‹Conductivity.›[A] 4-molar 0.17 1 1. 2-molar 0.22 1.30 1.30 1-molar 0.26 1.53 1.18 0.5-molar 0.30 1.76 1.15 0.25-molar 0.31 1.83 1.04 0.125-molar 0.32 1.88[B] 1.03 TABLE NOTES: A. This is an artificial scale (see text) of conductivities, and does not represent reciprocal ohms, the standard units of conductivity. B. In the exact data on the conductivities of 4-molar and 1/8-molar HCl (Kohlrausch and Holborn, ‹Leitvermögen der Elektrolyte› (1898) p. 160), the ratio 348 / 181.5, or 1.92, is found, in place of 1.88 as observed. We should expect, further, that the increase in conductivity, being dependent on the increased dissociation of a finite quantity of electrolyte, should tend towards a ‹limit›, a maximum conductivity being reached when (practically) all the acid is ionized. As a matter of experience, the conductivity of a given quantity of an acid or other ionogen does tend toward a ‹limit›. In the experiment just made, the conductivity of the acid increases very rapidly at first, as the 4-molar acid is diluted by water; but the increase in conductivity with the succeeding dilutions grows ‹smaller› and ‹smaller› and the conductivity is plainly approaching [p050] a limit (see the ratios I and II in the table). For hydrochloric acid at 18°, the limit for one mole[81] (36.5 grams HCl) at infinite dilution, as deduced from the curve of conductivities at finite dilutions, is 384 reciprocal ohms.[82]