( 192 ) 



tarigeiil, l>iil no vertical taiigeiils, l)ul it iiuiy still be i'emarked of 

 this iiielting-point line that it is the tirst that pursues its course 

 undisturbed up to the melting-point of anthraquinone. The nielting- 

 [)oint lines corresponding to higher pressures also proceed nninter- 

 ruplcdly from the eulectic point to (he melting-point of anthraquinone, 

 but they present a point of iiilloclion as sole peculiarity. 



. , , . ,..,, Anorq. Ckem. Laboratory 



Amsteraaiii, June 1911. ^' . •' 



of the Umvcrsifi/. 



Chemistry. — "U/i the .^ystoit iraler-pheno/." By Prof. A. Smits 

 and J. Maaksk. (Communicated by Prof. A. F. Hoi.leman.) 



Though the system water-phenol has already' several times been 

 the subject of in^•estig•ation, and already many peculiarities of the 

 mutual conduct of these substances have been revealed, it yet seemed 

 woilli while once more to take this system in hand, and determine 

 the melling-point ligure, the more so as we had come across a 

 hydrate of phenol that had drawn Cai.vkrt's^) attention already long 

 l)efore, but had not been met with by Patkkno and Ampola') in 

 their determination of the melling-point line of phenol in the system 

 water-phenol. 



In his paper entitled V IJeher e'm kri/stalUsirtes Hydrat? des 

 Phenols" Calvkrt writes as follows: "Schiittelt man 4 Theile Phenol 

 mit 1 Tlieil Wasser gut durcli einauder und kiililt man das Ge- 

 menge auf 4° ab, so bedecken sich die Wande des Gefasses mit 

 feinen sechsseitigen rhombischcn Prismen. — Dieser neue Körper lost 

 sich in Wasser, Alkohol und Aether und schmilzt bei 1(5°. Die 

 Analyse der zwischen Fliesspapier abgepressten Krystalle fiihrte zur 

 Formel C.,H,0., -f HO" '). 



After all Calvert, however, seems not. to have been perfectly 

 convinced of the existence of this hydrate, for in the title he placed a 

 note of interrogation after the word Hydrat. — Now it will appear from 

 what follows, that Calvert really had come across a hydrate of phenol 

 and that Patkrno and Ampola have quite overlooked this compound 

 in consequence of the circumstance that the formation of this hydrate 

 very often does not take place, so that very easily metastable states 



1) Zeitscbr. f. Chemie 1, 530 (1865). 



'-) Gazz. Ghim. ital. 27, 523 (1897). 



'^ RiNKES (Thesis for the doctorate Amsterdam 1910 and Re. 30) has availed 

 himself of this circumstance for the preparation of perfectly pure phenol, as the 

 hoinologueb of phenol do not give hydrates, as far as we know. 



