Am.  Jour.  Pharm  \ 
June,  1877.  J 
Collodion, 
301 
becoming  more  diluted.  If  charged  with  odorous  principles  it  may  be 
passed  through  charcoal  and  afterwards  rectified  by  redistillation,  or  it 
may  be  rectified  at  once  with  the  addition  of  some  permanganate, 
whereby  many  volatile  odorous  principles  are  destroyed. 
COLLODION. 
By  G.  H.  Chas.  Klie. 
The  {C  Pharmacopoeia  "  directs  to  make  simple  collodion  by  taking 
two  hundred  grains  of  pyroxylon,  and  by  occasional  shaking  to  dissolve 
it  in  a  mixture  of  twelve  and  a  half  fluidounces  of  stronger  ether,  and 
three  and  a  half  fluidounces  of  stronger  alcohol.  Cantharidal  collodion 
contains  in  one  pint  fifteen  fluidounces  of  an  ethereal  tincture  and  one 
ounce  of  a  concentrated  alcoholic  tincture  of  cantharides,  with  one 
hundred  grains  of  pyroxylon.  The  addition  to  this  of  one  hundred 
and  twenty  grains  of  Canada  turpentine  and  one  hundred  and  sixty 
grains  of  castor  oil  is  directed  to  insure  flexibility. 
With  soluble  pyroxylon  the  preparation  of  simple  collodion  offers  no 
difficulties  whatever  ;  that  of  cantharidal  collodion  offers  none,  after  a 
full  strength  spirituo-ethereal  tincture  has  been  secured.  The  success 
in  making  both  preparations  depends  on  the  solubility  of  the  pyroxylon. 
A  variety  of  methods  are  followed  in  the  preparation  of  this  article, 
besides  those  which  the  "  Pharmacopoeia  "  gives. 
One  formula  is:  Take  10  fluidounces  of  sulphuric  acid,  sp.  gr. 
1*84  in  a  dish,  add  12  fl.  drachms  of  water  and  10  fluidounces  of  nitric 
acid,  sp.  gr.  1*50,  and  raise  the  temperature  to  1400  by  immersing  the 
dish  in  boiling  water.  One  ounce  of  clean  cotton  is  then  immersed 
in  small  portions  at  a  time,  keeping  the  liquid  in  motion  until  the  liquid 
be  nearly  absorbed.  Wash  in  water  until  perfectly  neutral,  and  for 
preservation  dry  slowly  and  thoroughly.  I  have  tried  this  formula,  but 
without  success. 
Another  is  :  Take  of  cotton  one  ounce  ;  sulphuric  acid  five  fluid- 
ounces  ;  nitric  acid  five  fluidounces.  Mix  the  acids  in  a  porcelain 
mortar,  immerse  the  cotton  in  the  mixture  and  stir  it  for  three  minutes 
with  a  glass  rod  until  it  is  thoroughly  wetted  by  the  acids.  Wash  in 
water  until  the  washings  cease  to  give  a  precipitate  with  chloride  of 
barium.  Drain  the  product  on  filtering  paper  and  dry  in  a  water  bath. 
A  comment  accompanies  this  formula,  saying  :    "  The  officinal  nitric 
