12 C. E. FAWSITT. 



is given below, both in tabular form and in a spiral form. 

 The present Table (I) is a great change on the table as 

 known, say ten years ago. 



Periodic Classification of Elements. 

 The possibility of naming definitely the vacant places 

 (five) between aluminium and uranium would not have been 

 thought of ten years ago, and it may also be said to be 

 unlikely that there are vacant places between hydrogen 

 and aluminium. The changes that are introduced here in 

 the older Periodic Table are as follows: — 



(1) It is not now possible to believe that there is any vacancy for 



an (inert) element between nickel and copper or between 

 palladium and silver. It is therefore, I think, not advisable 

 to retain a special column for the inert gases. They are here 

 put in the same column as the elements iron, nickel, palla- 

 dium, etc. 



(2) Every element, or rather, each place for an element is num- 



bered. This number is the "Atomic Number." There is no 

 doubt that, in the light of recent work, iron, cobalt, nickel, 

 and each of the platinum group of elements require a separate 

 place or atomic number. The atomic number appears to 

 correspond or to be closely related to the net positive charge 

 on the nucleus of the atom. 



(3) For the places numbered 81 to 92 inclusive, it is necessary to 



give, besides the more important element, other radioactive 

 elements which have identical chemical properties. The 

 atomic weights of some of these are not known with great 

 accuracy and the atomic weights given are put in brackets. 



(4) Hydrogen is placed in the same column as fluorine. This 



arrangement is not ideal, but is preferable to leaving it out 

 of the table altogether, or putting it in the same column as 

 lithium, and so suggesting without any evidence that there 

 are elements (undiscovered) between hydrogen and helium. 



