Arsenical  poisoning  differs  from  lead  poisoning  in  being  seldom  the  result
of  occupation.  It  has  generally  been  due,  in  some  way,  to  the  use  of  pig-
ments containing  arsenic,  and  has  been  produced  through  the  agency  of
paints,  wall  papers,  book  covers,  etc.  The  poison  differs  from  lead  in  being
more  readily  diffused  through  the  air,  and  taken  in  by  the  lungs.  Some
interesting  facts  regarding  these  accidental  causes  have  been  collected  by
the  Medical  Society  of  London.*     Extensively  as  arsenic  is  used  in  medi-

*Proc.  Med.  Soc.  Lon.,  1880.
ARSENICAL   POISONING.  1273

cine,  toxic  effects  (beyond  a  little  conjunctivitis  and  gastric  irritation)  are
almost  unknown  when  it  is  administered  in  ordinary  doses.  One  case,
indeed,  is  on  record  in  which  severe  symptoms  were  produced  by  the
medicinal  administration  of  arsenious  acid,*  and  another  in  which  they
resulted  from  Fowler's  solution,  but  this  was  given  in  increasing  doses  up  to
ifss  three  times  a  day.f  There  is,  however,  no  doubt  that  those  who  are
taking  arsenic  often  suffer  from  herpes  zoster,  especially  on  the  trunk.  This
was  first  pointed  out  by  Hutchinson,  and  I  have  seen  at  least  a  dozen
instances  of  it.
