278 Dr. A. Goldhammer on the Analytical Representation 

 atomic weight p in the form 



<? = <2COt77 ■ , (1) 



where a is an unknown constant, and b and c are constants 

 easily determined for each period. 



The views of the two authors differ somewhat; whilst 

 F. Flawitzky, in agreement with L. Meyer *, considers V, Cr, 

 Mn, No, Mo as electronegative or acid-forming, and Cu, Zn, 

 Ga, Ag-, Gd, In as positive, according to Thomsen V, Cr, 

 Mn, Nb, Mo are electropositive, and Cu, Zn, Ga, Ag, Cd, In 

 negative ; from this it follows at once that Mendeleeff's eighth 

 group of positive metals, Fe, Co, Ni, Hu, Rh, Pd, Os, Ir, Ft, 

 must be left out of consideration by F. Flawitzky, whilst 

 J. Thomsen takes these metals into consideration. 



F. Flavvitzky remarks further that in his method of repre- 

 sentation N, 0, F appear just as well as analogues of P, S, 

 CI, As, Se, Br, Sb, Te, I, as of V, Cr, Mn, Nb, Mo, — -, Di, 

 — , — , Ta, W, which latter analogy is true in fact only in a 

 remote sense ; according to Thomsen, on the other hand, this 

 is not the case, since the elements analogous to V, Cr, Mn, 

 &c, ought to fall into the period Li — F between B and 0, 

 and in that from Na — CI between Al and Si. 



If we might take these views of J. Thomsen as valid be- 

 yond dispute, then the question of the analytical representation 

 of the periodic system of the elements would be nearly solved. 

 But if we hold with the views of L. Meyer the matter is 

 somewhat different ; the cotangents can then serve only as a 

 rough approximation to the truth. 



Since I, as a physicist, cannot venture to enter upon details 

 of chemical views, I permit myself here to show only by way 

 of experiment how the general character of the chemical 

 elements as given by L. Meyer may be represented geometri- 

 cally or analytically. 



In the system of Mendeleeff we have, as is well known, 

 six periods : Li— CI ; K— Br; Rb— I ; Cs— ? ; ?Bi ?; ? — ?. 

 After the electropositive alkaline metals Li, Be we have in 

 the first period a gradual passage through B, C to the electro- 

 negative acid-forming N, 0, F ; from F a rapid passage to 

 the positive Na, Mg, and then again after Al, which has some 

 claim to possess negative properties, a series of more and 

 more decidedly negative elements Si, P, S, CI. 



From CI to the positive K, Ca, Sc we have obviously a leap 

 in the properties of the elements ; then follow negative V, the 

 partly negative partly positive Cr, Mn, positive Fe, Co, Ni, 



* L. Meyer, Die modernen Theorien der Chemie (4th ed. 1880), i, 

 p. 167-169. 



