378 
EDITORIAL. 
arid  that  those  of  each  group  mostly  form  an  ascending  series,  in  which  each 
successive  member  contains  the  same  number  of  carbon  and  hydrogen  atoms 
as  the  preceding.  But  whilst  the  radicals  of  one  group,  in  their  combining 
proportions,  are  allied  to  hydrogen  and  the  positive  metals,  those  ol  another 
agree  in  this  (elation  with  the  negative. 
Jn  all  the  radicals  of  the  hydro-carbyls  may  be  distinguished,  1.  The 
Active  Element  or  Molecule:  and  2.  The  Ascending  Passive  Component,  by 
which  individual  members  of  a  group  are  formed.  In  all  Organic  Radicals 
which  have  a  positive  character,  the  active  part  is  H :  in  the  Negative  CiH. 
The  ascending  passive  member  of  the  Component  is  always  Ciffo.  All  radi- 
cals which  appear  as  simple  combinations  of  the  components  CzH;,  with  the 
active  H,  or  C.H,  form  the  class  of  the  Hydroisocarbyls,  but  if  between  the 
ascending  C2H2  and  the  active  H  or  CoH,  another  molecule  of  carbon 
enter.s=C2,C.i,C6,C8,  which  may  be  considered  as  a  Nucleus,  we  thus 
obtain  the  HydropolycarbylsV 
The  chapter  on  the  formation  of  organic  compounds  possesses  much  in- 
terest. The  formation  of  organic  compounds  occurs,  either  by  the  decom- 
position of  inorganic  compounds,  1st,  by  the  vital  action  of  plants  with  the 
co-operation  of  light ;  and  2d,  by  strictly  artificial  chemical  means  ; — or  it 
arises  from  the  decomposition  of  organic  compounds  ;  either  by  1st,  elec- 
trical influence ;  2d,  by  the  effect  of  heat ;  3d,  by  fermentation  and  putre- 
faction; 4th,  by  the  vital  functions  of  the  animal  organism; — or  by  the  agency 
of  chemically  reacting  matter.  The  following  quotations  from  pages  42 — 45, 
will  repay  the  reader. 
"The  inorganic  materials  for  the  formation  of  organic  compounds  under  the 
influence  of  the  vitality  of  plants,  are  carbonic  acid,  water  and  ammonia. 
As  is  known,  the  lower  plants,  as  the  fungi,  consist  of  single  cells,  each  of 
which  represents  the  plant  itself  ;  by  the  union  of  these  cells  the  cellular 
tissue  of  the  higher  plants  is  formed.  These  cells  are  the  most  important 
organs  of  plants;  in  them,  under  the  action  of  the  sunlight,  and  particularly 
of  the  yellow  and  green  rays,  the  formation  of  the  organic  compounds  takes 
place.  The  green  parts  of  plants,  particularly  the  leaves,  possess  the  power 
of  decomposing  water  and  the  carbonic  acid  of  the  air ;  consequently  over- 
coming the  original  affinities  by  which  the  elements  in  these  combinations 
are  united,  and  of  uniting  the  carbon  of  carbonic  acid  with  the  hydrogen  of 
water,  to  form  organic  radicals  or  molecules,  which  either  combine  with  each 
other,  or  unite  with  one  part  of  the  oxygen  withdrawn  from  carbonic  acid 
and  water,  whilst  the  other  part  escapes  into  the  atmosphere.  In  most  cases 
the  volumes  of  oxygen  gas  set  free  are  equal  to  the  volumes  of  carbonic 
acid  absorbed  by  the  plants;  and  if  this,  in  the  formation  of  certain  organic 
compounds,  is  not  the  case,  yet  the  result  in  the  Entire  vegetable  kingdom 
will  agree  with  the  above.  Plants  prevent  the  accumulation  of  carbonic 
acid  in  the  air,  and  mainly  cause  the  atmosphere  to  remain  the  same.  It  is 
true  the  leaves  absorb  oxygen  during  the  night,  and  evolve  carbonic  acid  ; 
yet  the  parts  of  plants  not  green  receive  oxygen  by  day  and  night,  and 
thence  give  forth  carbonic  acid.  But  the  quantity  of  oxygen  gas  which  the 
plants  use  in  the  formation  of  carbonic  acid,  is  much  less  than  that  which 
the  green  parts  of  the  same  emit  by  day.  If  the  constituents  of  ammonia, 
which  by  continual  decomposition  of  animal  matter  arises  in  great  quan- 
tities, take  part  at  once  in  the  formation  of  organic  compounds,  so  arise  nitro- 
genous organic  radical^.  A  part  of  the  material  which  is  necessary  to  the 
existence  and  growth  of  plants,  they  also  obtain  from  the  residue  of  organic 
matter  already  attacked  by  decomposition,  without  previous  formation  of 
