98 



Mr. Hermans, who iiiMlerfook tlii.s investigation (c.f. followino- com- 

 munication) soon succeeded in clearing up the composition ot' these 

 compounds. • 



The empirical formula KB0,(C8H,), applies to (he heaiitit'iilly 

 crystallized potassium salt; the volatile anuDoniuui salt is 

 NH,BO,(C.HJ,. aniline salt C,H,NH,HBO,(C,HJ„ from which through 

 careful heating in vacuum, the free acid HBO^(C,H,), (prepared and 

 analysed Ijy Mr. Meulenhoff) was obtained. 



There are, accordingly, two pyrocatechol rests bound to the boion 

 atom, in which an entirehj neiü type of compoiimls oritjinates, as 

 the potassium salt hardly reacts alkalically, and, as has been known 

 for a long time already, the relatively strong acid nature of the 

 hydrogen derivative manifests itself in aqueous solution by increase 

 of the conductivity. 



In view of the empirical constitution and this modification of 

 properties the below-given structural foi'mula naturally suggests 

 ., ,v /'\^ itself, in which we must imagine the 



anion of a relatively strong acid to have 

 arisen through binding of the fourth 

 K ^'^ oxygen atom to the boron. The acid is 



partially hydrolysed by water, but can be sublimated undecom|)osed 

 in anhydrous condition. Also in its spatial structure the anion will 

 be an antipode to the kation of the ammonium compounds; the 

 four atoms will lie in the four angles of a tetrahedron, and the 

 two benzene rings then are vertical to each other. 



The discovery of this type of boron compounds throws light 

 on the composition of a great numbei- of other boron compounds, 

 and indirectly gives a powerful support to the recent considerations 

 on the atomic structure in general. In tiiis connection we must 

 devote a few words to Lewis ') and Langmuir's ') atomic model, and 

 to the natural system of elements according to Kossei. '). 



Very much simplified and somewhat modified *) these hypotheses 

 come to what follows: 



The atom is assumed to be a positive nucleus surrounded by 

 different shells of electrons, in which the number of electrons must 



-0/" No 



i) G. N. Lewis. Journ. Am. Gh. Soc. 38 762 (1916). 



■) Irving Langmuir ibid 41 868 (1919) and 42, 274 (1920). 



S) Ann. der Physik 49 229 (1916). 



*) I wish to state here emphatically that I apply these considerations exclusi- 

 vely to the first period of the system, because 1 consider the atoms of the second 

 period already to be too complicated to satisfy the simple postulates. 



