The Results.

The following table contains the results of ten successive determinations.

			At. Wt. Cd.	At. Wt. Cd.
	Wt. of Cd.	Wt. of CdO.	(O = 16)	(O = 15.96)
I	1.77891	2.03288	112.070	111.790
II	1.82492	2.08544	112.078	111.798
III	1.74688	1.99626	112.078	111.798
IV	1.57000	1.79418	112.053	111.773
V	1.98481	2.26820	112.061	111.781
VI	2.27297	2.59751	112.059	111.779
VII	1.75695	2.00775	112.086	111.806
VIII	1.70028	1.94305	112.059	111.779
IX	1.92237	2.19679	112.083	111.803
X	1.92081	2.19502	112.078	111.798
Mean,			112.0705.	111.7905.
Maximum,			112.086.	111.806.
Minimum,			112.053.	111.773.
Difference,			.033.	.033.

Calculating the atomic weight of cadmium from the total amount of metal used and oxide found, we have:

At. Wt. of Cd.	At. Wt. of Cd.
(O = 16)	(O = 15.96)
112.0706.	111.7904.

These results agree more closely with those of von Hauer and Lenssen than with those of any other experimenter. The following table gives a comparison of the work of these investigators with that herein described:

	von Hauer.	Lenssen.	Work here described.
	9 determinations.	3 determinations.	10 determinations.
	(O = 16)	(O = 16)	(O = 16)
Mean	111.940	112.067	112.0705
Max.	112.121	112.304	112.086
Min.	111.796	111.911	112.053
Diff.	.325	.393	.033

A difference of three or four tenths of a unit between the different results of a series leaves considerable doubt as to the accuracy of the method employed and to the value obtained.

The figure selected by Ostwald,[5] as most probable for the atomic weight of cadmium is 112.08. This is the mean of the results on von Hauer and Huntington. My own work leads me to believe that this number is very close to the true value when oxygen is taken as 16.