"i.  The  combining  quantity  of  a  compound
is  the  sum  of  the  combining  quantities  of  its
components."     (Fownes.)

There  is  a  remarkable  relation  between  the
specific  gravity  of  a  body  in  the  gaseous  state


and  its  chemical  equivalent  or  combining  pro-
portion— a  relation  of  such  a  kind  that  quan-
tities by  weight  of  the  various  gases,  expressed
by  their  equivalents,  or,  in  other  words,  quan-
tities by  weight  which  combine  occupy,  under
similar  circumstances  of  pressure  and  tempera-
ture, either  equal  volumes  or  volumes  bearing
a  simple  proportion  to  each  other.  This  rela-
tion accounts  for  the  law  of  combination  by
volume  discovered  by  Gay-I<ussac,  and  thus
expressed : —

When  gases  combine,  chemical  union  in-
variably takes  place,  either  between  equal
volumes  or  between  volumes  which  bear  a
simple  relation  to  each  other.
Gerhardt  assumes  that  equal  volumes  of  the
elementary  gases  and  vapours,  when  compared
under  similar  conditions  of  pressure  and  tem-
perature, contain  the  same  number  of  atoms.
Consult  the  chemical  works  of  Fownes,  Ros-
coe.  Watts,  &e.  See  Affinity,  Atomic
Theory,  Equitalbnts,  &c

COMPOUND  CHINESE  TABLET  OF  ALA-
BASTER (Johnlrvine),  A  cosmetic  powder
for  the  skin.  It  consists  of  chalk,  free  from
injurious  metals.     (Chandler).
Compound  Chinese  Tablet  of  Alabaster
(Shand).  Identical  in  use  and  composition
with  the  last-mentioned  powder,

COMPOUND  SUGAE-COATED  MiT-APPLE
PILLS  (Dr  Scott).  Recommended  as  "anti-
bilious,  cathartic,  chemical  family  pills."
Sugar-coated  pills,  consisting  of  bitter  ex-
tract, powdered  podophyllum  root,  rhubarb,
jalap,  and  pepper.     (Hager).
COMFEESSES  DESINFECTANTES  DE  LE
PEEDEIEL.  Charcoal  powder  incorporated
with  paper.
CONCENTEATED  CASTOE  OIL  in  Capsules
of  Gelatin  (Taylor).  24  gelatin  capsules  filled
with  castor  oil,  containing  '5  per  cent,  of
croton  oil.     (Hager).
