Ar 
Fibu,r"if79?rm  }  Detection  and  Determination  of  Alcohol  91 
was  diluted  with  water  only,  the  effect  of  the  presence  of  other  sub- 
stances was  tried.  Stiideler  has  shown  that  albumin,  fibrin,  gelatin, 
and  lactic  acid,  yield  a  trace  of  aldehyd  when  treated  with  sulphuric 
acid  and  bichromate  of  potash,  or  peroxide  of  magnesia,  hence  these 
compounds  must  be  removed  from  solution  before  the  test  is  applied. 
No  substances,  with  these  exceptions,  besides  the  ethyl  compounds 
are  known  to  yield  aldehyd  when  thus  treated.  Various  essential 
oils,  chloroform,  amyl  alcohol,  etc.,  were  shaken  with  water  and  the 
solution  distilled  with  these  oxidizing  agents,  but  no  yellow  color  was 
produced.  The  distillate  from  clove  water  was  pink,  but  when  *i  per 
cent,  of  alcohol  was  added  the  pink  tint  was  quite  overpowered  by  the 
yellow  color  of  the  aldehyd  resin  produced.  Ether  of  course  yields 
aldehyd  when  oxidized,  hence  this  test  will  not  serve  to  detect  alcohol 
in  ether.  To  detect  alcohol  in  essential  oils  and  chloroform,  agitate 
the  sample  with  an  equal  quantity  of  water,  and  when  the  aqueous 
solution  has  become  clear,  remove  with  a  pipette  and  distil  with  the 
bichromate  and  acid.  *5  per  cent,  is  thus  easily  detected.  The  sub- 
joined table  gives  the  results  of  several  quantitative  experiments.  Four 
cc.  of  the  substance  examined  were  shaken  vigorously  with  8  cc.  of 
the  dilute  acid  and  92  cc.  of  water,  and  when  clear  50  cc.  of  the 
acid  liquid  placed  in  a  flask  and  distilled  with  a  sufficient  quantity  of 
bichromate.  Ten  cc.  of  distillate  are  collected  in  a  tube  containing 
2  cc.  of  soda  solution  and  boiled,  diluted  and  nesslerized. 
Name,  etc.  Q^TWn  Bi^r°mate  Result. 
'  bolution  added. 
Oil  of  Lemons,          .           .           .  .           2  cc.  .  none. 
"            "       with  5  p.  c.  alcohol,       .  2    "  •  3-6  p.  c 
"       Rosemary  with  5  p.  c.  alcohol,  2    "  .    3-9  " 
"       Bergamotte,                     .           .  2    "  •  none. 
"              "          with  10  cc.  alcohol,  2  "  .    97  p.  c 
"       Lavender,  English,           .           .  3^  "  .  none. 
"       Foreign,     .           .  .           3£  "  .    3  6  p.  c 
"  "  "       with  2^  p.  c.  alcohol,       3^  "  .  6-3  " 
"              "            "       washed,    .  .           3^  "  .  none. 
A  Pure  Chloroform,       .           .           .  2   "  .  a  trace. 
"           "           with  5  p.  c.  alcohol,  .            2  "  4-2  p.  c. 
with  1    '*        "    .  2   "  .  -92 
The  oil  of  lavender  (exot.)  was  undoubtedly  adulterated,  since  after 
being  washed  with  water,  and  examined,  no  reaction  was  obtained, 
