Am.  Jour.  Pharm. ) 
Feb ,  1877.  f 
N on- Actinic  Glassware, 
black  or  yellow  bottles  for  sensitive  substances,  as  chlorine  waterT 
calomel,  white  precipitate  and  the  two  iodides  of  mercury.  The 
writer  has  kept  both  chlorine  water  and  sulphuretted  hydrogen  water 
for  weeks  in  such  bottles,  exposed  to  daylight,  without  losing  their 
activity.  A  solution  of  nitrate  of  silver  has  purposely  been  kept  in 
the  show-window  (exposed  to  an  occasional  sun)  for  some  weeks,  and. 
was  found  as  clear  the  last  day  as  when  first  made.  Powdered  savin 
and  digitalis,  so  prone  to  change  their  green  color  to  a  dirty  yellow, 
keep  very  well  in  yellow  bottles.  Will  it  take  more  than  one  decade 
before  we  see  new  stores  fitted  up  with  amber  glass-ware  throughout: 
instead  of  white  ? 
Those  desirous  of  ascertaining  the  power  of  a  colored  glass  to 
exclude  obnoxious  rays  can  do  so  by  following  Le  Neve  Foster 
("  Brit.  Jl.  of  Phot.")  If  upon  a  dead-black  support  is  placed  a  narrow 
strip  of  white  paper  and  on  top  of  that  a  glass  prism,  the  colored  rays 
of  the  spectrum  will  be  seen  ;  if  now  a  colored  glass  be  placed  between 
the  prism  and  the  paper,  those  rays  which  the  glass  absorbs  will  have 
disappeared. 
Becquerel  mentions  a  curious  property  of  the  red  rays,  that  they 
continue  chemical  changes  if  only  commenced  by  the  blue  rays ; 
which  property  has  been  taken  advantage  of  by  the  earlier  daguerreo- 
typists  to  shorten  the  time  of  sitting.  The  same  author  mentions 
(loc.  cit.,  p.  268,  note)  that  Herschel  has  found  the  rays  which 
destroy  a  vegetable  color  to  have  the  same  refractive  power  as  those 
rays  which  are  of  a  color  complementary  to  that  of  the  vegetable. 
Note  by  the  Editor. — It  is  often  stated  that  brown-yellow  glass 
owes  its  color  to  finely  divided  carbon  ;  but  Pelouze  has  shown  (1865) 
that  the  same  color  is  produced  also  by  silicon,  boron,  aluminium,, 
calcium  phosphide  and  selenium,  and  depends  upon  the  formation  of 
an  alkaline  sulphide  from  the  sulphates  present.  In  regard  to  the 
action  of  light  upon  solutions  of  nitrate  of  silver  it  is  quite  possible 
that  the  amber-colored  glass  may  prevent  its  reduction  in  the  presence 
of  organic  matter  ;  but  solutions  which  are  free  from  the  latter  will 
keep  equally  well  in  glass  stoppered  flint  glass  bottles. 
