139 
tain more oxygen and less hydrogen than the alcohols, and 
which we call— 
C,H,O, C,H,O, C,H,0, 
Phloron, (Kreson), Chinon. 
I said in the case of phlorol; for, though we are able to pro- 
duce the other two compounds, the first by heating chinic 
acid, which in combination with lime is a constituent of all 
Peruvian barks, and the second by decomposing kresol, we 
will no doubt in time arrive at a proper method for obtaining 
them all directly, by treating the alcohols with nascent 
oxygen. 
In subjecting gum guajac to destructive distillation, we 
obtain a fluid which in many respects bears a great resem- 
blance to creosote. This distillate has been investigated 
especially by Volckel and Lobrero and Hlasiwetz, who suc- 
ceeded in separating it into two fluids, that gave crystalliza- 
ble compounds with bases, and which they called guajacol 
and homo-guajacol. A later and closer study of creosote 
revealed the fact, that it consisted of those two identical com- 
pounds in different proportion. Let us compare them with 
the products, we obtained from the alcohols of the phenylic 
series : 
C,H,O, (Chinon) C,H,O, (Kreson) 
C,H,O, (Hydrochinon and Pyrocat.) C;H,0, (Guajacol) 
C,H,O,  (Phlioron.) 
C,H,,O0, (Homo-guajacol or Creosote). 
But we have also the member corresponding to the chinon 
in a compound called Pyrocatechin, thereby completing two 
series of compounds, which differ only by the addition ot 
two equivalents of hydrogen. If we treat chinon with hy- 
drogen, we obtain directly hydrochinon; the attempt made 
in this direction with the others, succeeded perfectly, so that 
we possess another series of homologues— 
Hydrochinon, 
Hydrocreson, 
Hydrophloron, 
of exactly the same composition as— 
Pyrocatechin, 
Guajacol, 
Kreosol, 
but differs in properties. 
Now let us look at the constitution of those compounds. 
