400 
horsley's  test  for  strychnia. 
may  be  placed  on  a  clean  white  wood  table  or  board  to  drain. 
If  a  number  of  prints  have  been  treated,  the  wet  mass  may  be 
placed  in  a  warm  room,  or  air  may  be  admitted,  and  as  the  one 
on  the  top  of  the  pile  becomes  more  dry  than  the  rest,  it  may  be 
removed  to  any  support  and  left  to  dry.  In  hastening  the  drying 
I  have  extended  ordinary  bed  sheets  and  spread  the  wet  prints 
singly  on  these,  slow  drying  rendering  any  pressing  unneces- 
sary. 
Those  having  the  usual  presses  might  prefer  to  press  the  still 
damp  sheets,  and  where  only  two  or  three  prints  are  the  subjects 
of  trial,  the  substitution  of  other  vessels  and  ready  appliances 
will  occur  to  any  one. 
This  description  is  given  in  detail  purposely,  although  unne. 
cessary,  so  far  as  the  process  is  concerned,  because  I  wish  to  im- 
press on  the  mind  of  any  one  who  possesses  an  injured  engra- 
ving that  it  can  be  restored  to  its  original  value  without  the  ex- 
penditure of  much  attention  ;  and  it  must  not  be  the  conclusion, 
from  reading  this  process,  that  great  care  is  required,  for  time 
is  insisted  on  rather  than  attention.  The  few  dispositions  being 
made,  not  the  slightest  care  need  be  given  to  the  matter.  If  the 
bath  can  be  spared,  the  odd  minutes  of  a  week  will  enable  one 
to  restore  dozens  of  specimens,  and  give  permanency  to  their 
beauties. — Ohem.  Newss  July  26,  1862. 
HORSLEY'S  TEST  (?)  FOR  STRYCHNIA. 
Under  this  caption  Prof.  J.  E.  D.  Rodgers,  of  St.  George's 
School  of  Medicine,  criticizes  the  article  of  Mr.  Horsley  (see 
pages  433  and  434  of  this  number)  on  nitro-prusside  of  sodium 
as  a  test  for  strychnia,  and  asserts  that  Mr.  Horsley  must  have 
used  an  impure  test,  because  pure  nitro-prusside  will  not  cause 
such  a  reaction.  Mr.  Horsley  appears,  from  his  own  admissions, 
according  to  Prof.  Rodgers,  (Chem.  News,  Aug.  2,  page  69,)  to 
have  used  a  nitro-prusside  solution  containing  ferridcyanide  of 
potassium  !  one  of  the  best  color  tests  of  strychnia  yet  known. 
Mr.  Horsley,  however,  now  claims  (Chem.  News,  July  26,  page 
56)  that  his  impure  test  owes  its  intense  delicacy  not  to  nitro- 
prusside  or  to  ferridcyanide,  but  to  some  substance  which  he  has 
not  himself  identified,  and  offers  to  furnish  samples  of  the  re- 
gent to  any  chemist  interested. — Editor  Amer.  Jour.  Pharm. 
