268 
Methods  of  Studying  Coal.        {  Al?-  J°ur-  Pharm. 
'  -7     °  *-      June,  1917. 
tion  of  the  ethyl  acetate  about  half  of  it  separated  as  crude  ellagic 
acid,  which  when  crystallized  once  from  alcohol  yielded  13  g.  of 
pure  acid  that  did  not  melt  at  3500.  The  mother  liquor  from  this 
separation  was  a  smear,  that  colored  ferric  chloride  solution  black, 
and  precipitated  a  gelatin  solution. 
The  part  soluble  in  ethyl  acetate  was  thoroughly  examined  but 
nothing  was  isolated. 
The  Alcoholic  Extract  of  the  Resin  yielded  15  g.  further 
of  ellagic  acid.  The  total  ellagic  acid  separated  amounts  to  1.2 
per  cent,  of  the  plant.  Neither  an  acid  hydrolysis  nor  a  potash  fu- 
sion gave  any  interesting  decomposition  products.  Neither  the 
ethyl  acetate  fraction  nor  the  alcoholic  extract  was  glucosidic. 
Kalamazoo,  Mich. 
METHODS  OF  STUDYING  COAL1 
HOW  A  NEW  METHOD  OF  REFINED  TECHNIQUE  HAS  RE- 
VEALED PLANT  RECORDS  TO  THE  INVESTIGATION, 
ESPECIALLY  WITH  REFERENCE  TO  THE  ORIGIN 
OF  COAL. 
By  E.  C.  Jeffrey. 
Coal,  since  it  is  a  mineral,  has  in  the  past  been  investigated  with 
the  aid  of  the  admirable  technical  processes,  which  have  been  devised 
by  the  mineralogist  and  petrologist  in  the  study  of  minerals  and 
rocks.  Fossil  plants,  also,  have  naturally  been  regarded  as  minerals, 
since  in  the  condition  ordinarily  studied  structurally  they  are  petri- 
fied: that  is,  infiltrated  or,  in  some  instances,  actually  replaced  by 
mineral  substances.  In  addition  to  the  relatively  scanty  petrified 
remains  of  fossil  plants,  which  have  previously  been  the  most  im- 
portant document  for  the  student  of  extinct  vegetations,  there  are 
huge  quantities  of  plants  of  former  epochs,  preserved  for  us  by  a 
more  or  less  complete  process  of  carbonization.  This  carbon- 
ization is  so  marked  in  some  instances,  that  it  is  obvious  that  the 
plant  remains  have  been  charred  previous  to  fossilization.  The  pres- 
ent writer  has  turned  his  attention  to  the  utilization  of  these  car- 
bonized remains,  in  connection  with  the  tracing  of  the  all  too  incom- 
plete geological  records  of  plants.    By  the  perfecting  of  processes 
1  Reprinted  from  Science  Conspectus,  Vol.  6,  No.  3,  1916. 
