58 
ON  THE  PURIFICATION  OF  COAL,  NAPHTHA,  ETC. 
out  any  result.  With  regard  to  the  theory  of  the  decomposi- 
tion which  took  place,  and  the  cause  of  these  explosions,  his 
impression  was  that  iodide  of  nitrogen  was. formed,  but  even  its 
formation  must  be  looked  upon  as  an  extraordinary  circumstance, 
when  we  bear  in  mind  the  small  quantity  of  nitrogen  contained 
in  these  alkaloids ;  and  what  is  more  extraordinary  still,  the 
inability  of  any  other  nitrogenized  body  to  produce  the  same 
reaction.  If  this  explosive  property  should  be  shown  to  belong, 
by  further  experiment,  as  he  had  no  doubt  it  would,  exclusively 
to  the  alkaloids,  it  would  be  an  important  addition  to  our  know- 
ledge of  these  powerful  medicinal  agents ;  for  instance,  if  we 
treat  an  unknown  white  substance  with  iodic  acid,  and  get  no 
explosion,  we  can  say  at  once,  that  body  is  not  one  of  the  alka- 
loids, and  as  far  as  he  had  tried  experiments  upon  the  salts  of 
the  alkaloids,  which  were  upon  sulphate  of  quinine  and  muriate 
of  morphia,  he  had  found  the  reaction  the  same  as  upon  the 
alkaloids  themselves. — Pharm.  Jour.,  Nov.  1854. 
ON  THE  PURIFICATION  OF  COAL  NAPHTHA,   AND  OTHER 
VOLATILE  HYDRO-CARBONS  CONTAINING  BENZINE. 
By  Professor  Calvert,  of  Manchester. 
Professor  Calvert  finds  that  pure  benzine  and  some  of  the 
volatile  hydro-carbons  obtained  by  the  dry  distillation  of  bitu- 
minous coals  and  shales,  which  also  contain  benzine,  possess,  to 
a  high  degree,  the  property  of  dissolving  fatty  or  oily  matters, 
and  proposes  to  apply  this  property  of  benzine  to  various  useful 
purposes. 
In  order  to  render  the  various  products  that  contain  benzine 
,  suitable  for  their  several  applications,  he  submits  them  to  the 
following  treatment,  the  object  of  which  is  to  destroy  or  remove 
some  of  the  carburetted  hydrogens  which  are  mixed  with  them, 
and  which,  not  being  sufficiently  volatile,  interfere  with  the  ap- 
plication of  benzine. 
To  effect  this  he  takes  coal  and  shale  naphthas,  preferring  the 
limpid  coal  naphtha  of  commerce,  and  puts  it  into  a  suitable 
earthenware  or  leaden  vessel,  and  adds  to  it  sulphuric  acid  in 
small  quantities  until  no  more  coloration  is  produced ;  conse- 
.  quently  the  quantity  of  acid  employed  will  vary  with  the  relative 
