CONSTITUTION  OF  COAL-TAR  CREOSOTE. 
55 
contain  a  greater  quantity  of  this  hydrate  of  cresyle  (as  it  may  be 
termed)  than  others ;  and  it  is  most  advantageously  prepared  from 
those  portions  which  in  the  first  distillation  come  over  between 
200°  Cent,  and  220°.  After  a  great  number  of  fractional  distilla- 
tions, a  colorless,  highly  dispersive  liquid  is  obtained,  boiling  at 
203°  Cent.,  and  possessing  the  composition  represented  by  the 
formula  C1JHH02. 
This  hydrate  of  cresyle  resembles  the  corresponding  phenyle 
compound  in  most  of  its  properties  ;  but  it  may  be  easily  distin- 
guished from  that  compound  by  its  almost  complete  insolubility  in 
aqueous  ammonia. 
When  gradually  mixed  with  sulphuric  acid,  it  becomes  of  a 
beautiful  rose-color,  and  gives  rise  to  sulpho-cresylic  acid. 
The  action  of  nitric  acid  upon  hydrate  of  cresyle  is  very  violent, 
and  almost  explosive  if  the  acid  is  used  in  a  concentrated  state 
and  at  so  high  a  temperature  as  the  common  atmospheric;  even 
very  dilute  nitric  acid  transforms  the  compound  into  a  brown  tarry 
mass  from  which  no  definite  substance  can  be  extracted.  By  cooling 
some  nitric  acid  in  a  frigorific  mixture,  and  allowing  some  simi- 
larly cooled  hydrate  to  fall  into  it  drop  by  drop  and  with  constant 
agitation,  a  red  colored  solution  was  obtained,  which  by  dilution 
with  water,  and  subsequent  neutralization  by  potash,  yielded  a  crop 
of  short  needle-shaped  crystals  of  an  orange-red  color  and  possess- 
ing a  greater  solubility  in  water  than  the  salt  of  carbazotic  acid. 
This  salt  was  found  by  analysis  to  possess  the  composition  of  a 
homologue  of  carbazotate  of  potash  ;  so  that  it  is  the  potash  salt 
of  a  hydrate  of  cresyle  in  which  three  atoms  of  hydrogen  are  re- 
placed by  hyponitric  acid, 
H4 
C14        0,  KO 
(NO4)3 
The  same  acid  was  obtained  by  the  action  of  nitric  acid  upon 
an  alcoholic  solution  of  the  hydrate  containing  urea;  but  in  at- 
tempting to  repeat  this  experiment  on  a  larger  scale  the  mixture 
became  hot,  and  the  whole  of  the  substance  was  destroyed  with 
almost  explosive  violence. 
When  treated  with  pentachloride  of  phosphorus  this  hydrate  of 
