462  Gleanings  from  the  German  Journals.  {Am,sJepty,'i89iarm 
color,  whereas  in  artificially  colored  oils  the  green  color  changed 
to  yellow. —  Chemiker  Ztg.,  1 891 ,  1023. 
Tonquinol. — (See  Am.  Journ.  Pharm.,  1891,  2S9.)  For  its  manu- 
facture equivalent  weights  of  oil  of  turpentine  and  isobutylalcohol 
are  mixed  and  slowly  added  to  5  or  6  times  its  volume  of  concen- 
trated sulphuric  acid,  preventing  any  rise  in  temperature  ;  after  one 
or  two  hours  this  mixture  is  poured  into  5-10  times  its  volume  of 
fuming  nitric  acid  ;  when  the  nitrating  is  complete,  the  mixture  is 
poured  into  a  large  excess  of  water  which  causes  precipitation  of 
the  nitro-derivative  ;  it  is  collected  on  a  filter  and  washed  to  neutral 
reaction.  It  forms  a  pale  yellow  powder,  of  strong  musk  odor, 
melting  at  700  C. — Pharm.  Centralhalle,  1 891,  459. 
Tanni?i  extraction. — A  patent  has  been  granted  the  firm  J.  D. 
Riedel,  of  Berlin,  for  the  following  method  :  The  properly  commi- 
nuted and,  if  necessary,  dried  material  is  placed  in  a  suitable  continu- 
ous extraction  apparatus  and  exhausted  with  a  solvent  for  resins^ 
waxes,  fats  and  chlorophyll  like  ether,  carbon  disulphide,  amyl  alcohol, 
benzol,  benzin,  etc. ;  by  heating  the  solvent  is  completely  removed 
from  the  material  and  the  tannin  then  extracted  by  percolation 
with  water;  by  dialysis  the  crystal] izable  salts  and  gallic  acid  are- 
removed  as  rapidly  as  possible  from  the  percolate  to  prevent  change 
in  the  tannin  and  then  the  dialyzed  solution  is  evaporated. — Pharm. 
Centralhalle,  1891,419. 
Oil  of  rose. — An  examination  of  the  German  as  well  as  the 
Turkish  oil  showed  that  both  contained  the  same  constituents 
although,  in  different  proportions :  (1)  Ethyl  alcohol  found  in  the 
fraction  boiling  between  70  and  ioo°  C;  (2)  Rhodinol,  this  constitutes 
the  bulk  of  the  oil  and  is  the  odorous  constituent ;  rose  oil  freed  from 
stearopten  contains  only  rhodinol  and  is  made  by  dissolving  the  oil 
in  five  volumes  of  75  per  cent,  alcohol  at  a  temperature  of  75-800 
C,  cooling,  with  constant  agitation,  to  0°  C,  filtering,  washing  the 
separated  stearopten  with  dilute  alcohol,  and  allowing  the  alcohol  to 
evaporate  in  vacuo  at  the  ordinary  temperature  when  the  purified 
oil  is  left.  If  rhodinol  be  distilled  in  quantities  greater  than  25-30 
gm.  as  much  as  25  per  cent,  will  resinify.  Rhodinol  has  the  specific 
gravity  0-8804-0*88 1 3  at  150  C;  is  slightly  laevogyre  ;  is  soluble  in 
alcohol,  ether,  chloroform,  benzin,  benzol,  carbon  disulphide  and 
glacial  acetic  acid ;  obtained  from  German  oil  it  is  of  a  green  color, 
from  the  Turkish  oil  of  a  yellow  color  ;  both  have  a  pleasant  odor 
