Am.  Jour.  Pharm. 
July,  1887. 
Ammonium  Iodide. 
337 
It  was  ascertained  that  acetic  ether  is  perfectly  satisfactory  as  a  de- 
colorizer,  but  it  also  dissolves  a  very  considerable  proportion  of  the 
salt.  On  treating  the  red  acetic  ether  solution  with  a  little  water,  two 
strata  are  formed.  The  upper  one  retains  most  of  the  free  iodine  and 
but  little  of  the  salt,  whilst  the  lower  one,  being  chiefly  aqueous,  con- 
tains most  of  the  iodide  and  some  free  iodine. 
Alcohol  does  not  wholly  decolorize  the  salt  whilst  it  also  dissolves 
too  large  a  proportion  of  it.  Chloroform,  benzene  and  benzin  were 
found  inapplicable  for  other  reasons  beside  lack  of  solvent  power  over 
the  adherent  iodine. 
At  this  juncture  it  seems  appropriate  to  say  something  about  the 
prevalent  nomenclature  attaching  to  the  two  substances  last  named. 
It  is  not  commonly  understood  that  benzin,  also  termed,  benzine, 
naphtha,  gasoline,  petroleum  spirit,  &c,  is  wholly  different  from  ben- 
zene, also  called  benzol,  and  benzole.  The  former  body,  which  might 
conventionally  be  termed,  benzane,  is  a  mixture  of  hydro-carbons,  be- 
longing exclusively  to  the  paraffin  series,  a  portion  of  the  so-called 
fatty  group.  The  latter  body,  benzene,  is  the  characteristic  member 
of  the  so-called  aromatic  group  of  hydro-carbons.  Still  another  con- 
fusion prevails  in  the  indiscriminate  application  of  classic,  ordinal  and 
generic  terms.  For  instance  the  fatty  group  as  a  whole  is  classed  as 
methane  derivatives,  although  methane  is  but  a  paraffin  and  although 
the  class  of  fatty  hydro-carbons  is  composed  of  the  orders  of  paraffins, 
olefines,  acetylenes,  terpenes,  &e. 
Then  in  addition  the  fatty  group  is  designated  as  parainnoids  and 
in  analogy  the  aromatic  group  is  styled  the  benzenoids,  a  nomencla- 
ture, which  is  as  incorrect  and  unsatisfactory  as  the  former.  Chemical 
and  physical  inferences  have  led  to  the  structural  symbolization  of  the 
fatty  hydro-carbons  and  derivatives,  as  so-called  open  chains.  That 
is  the  graphic  representation  of  the  main  axis  is  flat,  hence  they  might 
appropriately  be  termed  the  organic  homaloids.  For  pertinent  reasons 
the  members  of  the  aromatic  group  are  represented  as  closed  chains. 
Hence,  since  their  main  axes  are  recurved  upon  the  origin,  they  might 
with  equal  propriety  be  styled  the  organic  sphericoids.  But  inde- 
pendently of  this  nomenclature,  the  paraffins,  olefines,  acetylenes,, 
terpenes,  benzenes,  &c,  might  conveniently  and  correctly  be  known  as 
the  methanids,  ethenids,  ethinids,  terpenids,  benzenids,  &c.,  respec- 
tively. Hence  for  instance  a  terpenid  may  be  a  sphericoid  and  yet 
have  no  structural  relation  to  the  benzenids. 
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