Am.  Jour.  Pharm. ) 
July,  1878.  J 
Quiniretin. 
349 
of  quinia  not  to  expose  to  direct  sunlight  either  their  products  or  even 
the  barks. 
Carles1  exposed  powdered  Calisaya  bark  to  sunshine  during  the 
month  of  August,  and  found  it  to  yield  afterwards  less  quinia  than 
before.  Broughton2  likewise  pointed  out  the  detrimental  influence  of 
direct  sunshine  on  barks  collected  in  the  government  plantations  in  the 
Nilghiris. 
Hesse,3  on. the  other  hand,  stated  that  the  influence  of  light  was  by 
no  means  so  powerful,  and  did  not  favor  very  vigorously  the  formation 
of  amorphous  alkaloids.  He  exposed  for  seventy-three  days  to  sun- 
light an  aqueous  solution  containing  3-72  per  cent,  of  quinia  in  the 
form  of  sulphate.  Quinicia  was  found  to  be  at  last  contained  in  the 
liquor,  besides  a  red  amorphous  substance  no  longer  possessing  the  pro- 
perty of  neutralizing  the  acids.  Hesse  did  not  meet  with  the  latter  in 
the  barks  as  might  be  expected,  supposing  sunlight  to  act  in  the  same 
way  on  the  alkaloids  contained  in  the  tissue  itself. 
Mr.  David  Howard4  ascertained  that  quinicia  at  least  occurs  in  the 
mother-liquids  obtained  in  manufacturing  quinia,  and  Dr.  de  Vrij5  is  of 
the  opinion  that  not  only  quinicia  and  cinchonicia,  but  another  third 
amorphous  alkaloid  is  present  in  the  barks. 
The  influence  of  sunlight  on  the  latter  and  on  their  bases  is  a  very 
interesting  question,  as  shown  by  the  experiments  just  alluded  to.  They 
refer  not  to  the  alkaloids,  but  to  salts  of  them.  What  part  is  played 
by  the  acids  with  which  the  alkaloids  are  combined  ?  Are  the  alkaloids 
themselves  likewise  altered  by  sunshine  or  only  their  salts  ? 
I  thought  it  of  some  interest  to  submit  quinia  to  a  few  experiments, 
and  was  struck  to  see  how  rapidly  and  thoroughly  it  is  altered  ;  2,000 
parts  of  water  at  I7°C.  dissolve  a  little  more  than  1  part  of  quinia, 
yielding  a  clear  solution,  which  remains  colorless  and  clear  for  any 
length  of  time,  provided  it  be  kept  in  the  dark  or  in  dispersed  daylight, 
in  closed  or  in  open  phials.  But  on  exposure  to  sunlight  in  July  or 
August,  for  a  few  hours,  the  liquid  turns  yellowish  or  brownish,  the 
coloration  being  developed  uniformly  in  the  whole  solution,  not  begin- 
1<<Jour.  de  Pharm.,"  xii,  1870,  p.  161. 
2"Blue  Book,  East  India  Cinchona  Plantation,"  1870,  fol.  241,  243,  118. 
:1 "  Annalen  der  Chemie,"  clxvi,  1873,  P-  275- 
4  "  Pharm.  Journ  ,"  i,  1871,  p.  485,  and  ii,  1872,  p  765. 
&" Pharm.  Journ.,"  iv,  1874,  p.  589. 
