DEPRESSIONS FOR ELECTROLYTES—MACGREGOR. DG 
Arrhenius, Raoult,? Loomis,?Jones,* Abegg,® Wildermann,’ Ponsot,’ 
Archibald’ and Barnes®. The methods used by these observers 
are, for the most part, well known. Archibald and Barnes used 
modified forms of Loomis’s method.  Arrhenius’s observations, 
and some of Raoult’s, were made before important improvements 
in freezing-point determinations had been recognised as neces- 
sary. 
In eases in which there was but one series of observations 
available, I have plotted the actual observations in the diagram, 
though sometimes smoothing the curves a little. In cases in 
which two or more series were available, I first plotted the vari- 
ous observations, and then drew mean curves, making them 
represent all the observations as well as I could, but giving 
greater weight to recent observations than to those of earher 
date, and to long series of consistent observations than to short 
series, or to series which were more erratic. 
The following table gives the data employed in plotting both 
the curves given in the diagram, and those not so given, which 
are referred to below. The table includes the concentration in 
gramme-equivalents per litre, the ionization coefficient at 0°, and 
the equivalent depression in degrees centigrade per gramme- 
equivalent in one litre of solution. The interpolated coefficients 
are indicated by 7,and those extrapolated by e, and the observers 
from, or by the aid of, whose observations they were obtained, 
by A, B, D, W, representing Archibald, Barnes, Déguisne and 
Whetham. Non-significant figures are printed in italies. 
1 Ztschr, f. phys. Chemie. 2, 491, 1888. 
2 Tbid., 2, 501, 1888, and 27, 617, 1898. 
3 Phys. Review, 1, 199 and 274, 1893-4; 3, 270, 1896, and 4, 273, 1897. 
4 Ztschr. f. phys. Chem., 11, 110 and 529, 1893; and 12, 623, 1893. 
5 Tbid. 20, 207, 1896. 
6 Ibid. 19, 233, 1896. 
eae 7 Recherches sur la Congélation des Solutions Aqueuses: Paris, Gauthier- Villars, 
Bs fe Loe. cit. 
