^"'j^nZ'il)""'-}  Proximate  Analysis  of  Cinchona  Bark.  3 
Its  solution  in  concentrated  sulphuric  acid  becomes  carbonized  upon 
the  application  of  heat. 
With  hydrochloric  acid  no  change  of  color  takes  place,  either  in  the 
cold  or  upon  heating,  and  it  is  apparently  insoluble  in  this  liquid. 
If  a  drop  of  strong  nitric  acid  be  added  to  elaterin  upon  a  porcelain 
plate,  no  change  of  color  takes  place,  except  after  standing  for  several 
hours,  when  a  pinkish  tinge  is  observed  ;  but  upon  heating  it  v^ith  that 
liquid,  a  red  coloration  is  soon  produced,  with  the  evolution  of  nitric 
oxide  vapors,  and  upon  the  addition  of  water,  separates  white  flocks. 
It  undergoes  no  change  of  color  with  chlorinated  alkalies.  An 
alcoholic  solution  of  elaterin  is  not  precipitated  by  an  alcoholic  solution 
of  tannic  acid  or  barium  chloride.  When  heated,  it  melts,  giving  off 
white  fumes,  which  are  neutral  in  their  action  upon  litmus,  and  burns 
with  a  smoky  flame,  leaving  a  garnet-colored,  resinous  ash. 
A  prescription  was  recently  received  for  one  grain  of  elaterin,  to  be 
dissolved  in  a  fluidrachm  of  water,  for  hypodermic  injection;  but  being 
wholly  insoluble  in  water,  no  practical  method  could  suggest  itself  to 
the  mind  of  the  writer  whereby  such  an  application  could  be  obtained. 
Philadelphia,  December,  1874. 
NOTE  ON  THE  PROXIMATE  ANALYSIS  OF  CINCHONA  BARK. 
Limited  to  the  separation  of  the  four  alkaloids,  S^inia,  ^inidia,  Cinchonia  and  Cin- 
chonidia,  and  the  three  acids,  ^inic,  ^ino'vic  and  S^uinotannic . 
BY  ROBERT  M.  COTTON. 
The  process  given  below  is  nothing  more  or  less  than  the  com- 
bination of  methods  reported  by  different  authorities,  and  given  in 
Watts'  Dictionary  and  Gmelin's  Handbook,  modified,  in  some  particu- 
lars, after  trial.  The  writer  has  found  all  the  results  of  this  process  to 
be  satisfactory.  The  same  material  was  subjected  to  operations  by 
other  methods  without  obtaining  as  good  results. 
Any  desired  quantity — say  one-half  pound — of  the  powdered  bark  is 
macerated  with  warm  water  for  two  or  three  days  and  then  percolated, 
water  being  added  upon  the  percolator  to  exhaustion.  Hydrochloric 
acid  is  added  to  the  percolate,  to  a  distinct  acid  reaction  ;  then  solution 
of  caustic  soda  is  added,  with  stirring,  to  an  alkaline  reaction,  and  the 
mixture  is  set  aside  for  some  hours  for  subsidence  of  the  precipitate 
The  whole  is  then  filtered,  and  the  precipitate  well  washed  with  cold 
