ox ARGOX AXD ITS CO.MPAXIOXS. 
89 
General Rernarks .— The great value of Newland’s, Mexdeleef’s, and Lothar 
Meyer’s generalisation, known as the periodic arrangement of the elements, is 
universally acknowledged. But a study of this arrangement, it must be allowed. Is a 
somewhat tantalising pleasure; for, although the properties of elements do un¬ 
doubtedly vary cpialitatively, and, indeed, show approximate quantitative I'elations 
to their position in the periodic table, yet there are inexplicable deviations from 
regularity, which hold forth hopes of the discovery of a still more far-reaching- 
generalisation. What that generalisation may be is not yet to be divined; but that 
it must underlie what is known, and must furnish a clue to the explanation of 
irregularities, cannot be disputed. 
Fig. 9. 
When we began the search lor the elements ol which the physical properties are 
described in the foregoing pages, we Avere not without a strong hope that their 
discovery would solve the problem. For there can be little doubt that these inactive 
elements constitute simple, if not the simplest forms of matter. They have no 
tendency to form compounds, and are monatomic; their physical relations, we may 
therefore presume, are not subject to interference by the simultaneous exercise of 
chemical functions. But our hope has been fruitless. While the same rough 
quantitative correspondence between the order in the periodic table and the physical 
properties is manifest, as Avith other similar series of elements, Ave haAm failed to 
trace any simple mathematical expressions Avhich AA'ould make it possible to predict 
Avith accuracy the physical properties of any one of these elements, from a knoAAdedge 
of those of its congeners. It is possible that such expressions exist; aa'c venture 
to hope that others, more mathematically gifted than aa'g are, may succeed A\diere we 
have failed. 
YOL. CXCAUI.—A. 
X 
