new  Cafe  in  Squinting.  89 
A gnomon  of  thin  brafs  was  made  to  ftand  over  his 
nofe,  with  a half  circle  of  the  fame  metal  to  go  round 
his  temples;  thefe  were  covered  with  black  filk,  and  by 
means  of  a buckle  behind  his  head,  and  a crofs-piece 
over  the  crown  of  his  head,  this  gnomon  was  managed 
fo  as  to  be  worn  without  any  inconvenience,  and  pro- 
jected before  his  nofe  about  two  inches  and  an  half.  By 
the  ufe  of  this  gnomon  he  foon  found  it  lefs  inconve- 
nient to  view  all  oblique  objects  with  the  eye  next  to 
them,  inftead  of  the  eye  oppofite  to  them. 
After  this  habit  was  weakened  by  a week’s  ufe  of  the 
gnomon,  two  bits  of  wood,  about  the  fize  of  a goofe- 
quill,  were  blackened  all  but  a quarter  of  an  inch  at  their 
fummits;  thefe  were  frequently  prefented  for  him  to 
look  at,  one  being  held  on  one  fide  the  extremity  of  his 
black  gnomon,  and  the  other  on  the  other  fide  of  it.  As 
he  viewed  thefe  they  were  gradually  brought  forwards 
beyond  the  gnomon,  and  then  one  was  concealed  behind 
the  other:  by  thefe  means,  in  another  week,  he  could 
bend  both  his  eyes  on  the  fame  objecft  for  half  a minute 
together. 
By  the  practice  of  this  exercife  before  a glafs,  almoft 
every  hour  in  the  day,  he  became  in  another  week  able 
to  read  for  a minute  together  with  his  eyes  both  directed 
on  the  fame  objects;  and  I have  no  doubt,  if  he  has  pa- 
Vol.  LXVIIL  N tience 
