524        Recent  Literature  Relating  to  Pharmacy.  {Aro-ioberPi89asrm' 
SWEET  GUM  OIL. 
The  leaves  of  Liquidambar  styraciflua  L.,  have,  when  bruised,  a 
peculiar  turpentine-like  odor.  When  distilled  they  yielded  only 
0  085  per  cent,  of  oil,  having  a  greenish-yellow  color,  a  specific 
gravity  of  0-872,  the  optical  rotation  380  35',  the  saponification 
number  0-9,  and  the  acetylization  number  25-2.  The  oil  contains 
terpene,  borneol  and  bornyl  acetate,  and  the  odor  recalls  that  of  the 
oil  of  Abies  pectmata,  D.  C — Sckimmel's  Report,  1898,  p.  53. 
CHINESE  INSECT  WHITE  WAX. 
According  to  G.  F.  Smithers  (U.  S.  Consular  Reports,  1897,  p. 
484)  the  best  of  the  insects  {Coccus  pe-la)  that  produce  white  wax 
are  found  in  the  Chien-Chang  Valley.  Those  from  elsewhere  bring 
a  lower  price,  where  they  are  found  on  the  evergreen,  Ligustrum 
lucidum,  which  has  various  local  names,  as  ch'ung  shu,  or  insect 
tree;  tung  ching  shu,  or  evergreen  tree;  and  pao-ke-ts'ao  shu,  or 
crackling  flea  tree.  The  insects  from  Chien-Chang  Valley,  found 
for  the  most  part  near  the  town  of  Te  Chang  on  the  Au-ning  River 
(latitude  270  24'),  are  transported  to  the  plain  north  of  the  Ta-tu 
River  north  of  Chien  Chang,  where  they  are  placed  on  the  wax 
tree,  Fraxinus  chinensis,  known  to  the  Chinese  as  the  pai  la  shu. 
One  pound  of  the  scales  produces  4  to  5  pounds  of  wax.  The  pro- 
cess of  obtaining  the  wax  is  described. 
ASSAY  OF  SYR.  IODIDE  OF  IRON. 
Ralph  S.  Swinton  (Chem.  and  Drug.,  1898,  p.  837)  proposes  the 
following  :  Dilute  10  c.c.  of  the  syrup  with  90  c.c.  water;  slowly  mix 
10  c.c.  of  this  solution  with  5  c.c.  of  strong  sulphuric  acid,  keeping 
the  vessel  cool  by  allowing  a  stream  of  cold  water  to  flow  over  it. 
When  nearly  cold,  thoroughly  agitate  the  mixture  with  5  c.c.  of 
phenol  (90  per  cent.),  then  with  25  c.c.  of  a  completely  saturated 
bromine  water ;  remove  the  separated  iodine  by  washing  out  with 
chloroform  (two  washings  usually  suffice),  treat  the  mixture  again 
with  phenol-bromine,  separate  the  iodine  as  before  and  mix  with 
the  first  portion.  The  whole  chloroformic-iodine  solution  is  now 
covered  with  a  layer  of  water  and  titrated  with  decinormal  sodium 
thiosulphate,  with  starch  paste  as  an  indicator.  1  c.c.  decinormal 
sodium  thiosulphate  =  0-0155  gm.  Fel2.  The  whole  process  occu- 
pies only  a  few  minutes  and  is  accurate. 
