186 
JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER . 
March  4,  1897. 
enabling  us  to  secure  some  thousands  of  plants  to  form  large  beds 
in  the  long  border  we  had  to  fill.  When  the  varieties  of  Sweet 
William  (Dianthus  barbatus)  were  distinguished  by  names  like 
other  florists’  flowers,  increase  by  cuttings  or  layers  was  necessary, 
and  raising  a  large  supply  was  a  rather  tedious  business  ;  matters 
are  very  different  now,  however,  for  the  attention  paid  to  the 
improvement  of  seed  selection  has  resulted  in  a  great  advance.  It 
is  no  exaggeration  to  say  that  from  a  packet  of  the  best  seed,  such 
as  that  sent  out  by  all  the  leading  houses,  it  is  possible  to  have 
numbers  of  varieties  quite  up  to  the  old  florists’  standard  as  regards 
size,  regularity,  and  colour  of  the  flowers. 
Familiar  as  we  have  long  been  with  the  advance  made  in 
the  mixed  seed  strains  of  popular  flowers,  we  have  repeatedly 
been  astonished  by  the  high  quality  of  the  seedling  varieties  thus 
obtained  amongst  Sweet  Williams.  Many  a  bed  we  have  had  that 
presented  quite  a  study  in  itself,  both  for  range  of  variation  in 
colouring  and  aize  ;  the  individual  flowers  even  and  bold,  the 
trusses  large,  compact,  and  effective.  Because  they  are  “  common  ” 
-flowers,  they  are  yet  by  no  means  “  common  ”  as  regards  their 
attractions,  and  few  of  the  easily  grown  plants  present  so  many 
characters  worthy  of  note.  Nor  is  it  only  at  the  flowering  time 
that  the  plants  are  worthy  of  notice,  well- grown  busby  specimens 
are  ornaments  in  a  border  throughout  the  winter  months.  The 
vigorous  healthy  growth  is  in  a  measure  the  cause  of  this,  but  the 
tints  assumed  by  the  leaves  are  the  chief  feature. 
The  dark  and  light  coloured  flowers  are  respectively  attended 
by  dark  and  light  foliage,  and  in  the  former  case  the  leaves  become 
of  a  rich  bronzy  red  that  is  singularly  effective  when  there  is  little 
colour  in  the  hardy  plant  borders.  In  contrast  with  the  dark  red 
shades  we  have  various  tints  ot  green,  some  being  exceptionally 
bright  and  lively,  very  distinct  from  the  ordinary  greens  of  winter 
foliage,  and  more  resembling  the  fresh  hues  of  spring  buds. 
Such  are  some  of  the  attractions  of  these  plants,  but  no  one  can 
grow  them  in  quantity  and  with  the  object  of  studying  them 
without  discovering  other  qualities  of  interest. 
The  seed  should  be  sown  as  early  in  May  as  possible,  in  fact 
similar  treatment  to  that  needed  by  Wallflowers  is  requisite,  but 
we  have  found  this  difference — namely,  that  far  better  plants 
result  from  seedlings  only  once  transplanted  than  from  those  which 
are  shifted  twice.  The  sooner  the  seedlings  can  be  placed  in  the 
permanent  quarters  when  they  have  made  sufficient  advance  in  the 
seed  bed  to  be  easily  lifted  the  better  is  the  growth  produced 
before  winter  checks  their  progress.  It  is  also  important  to  sow 
the  seed  thinly,  and  even  then  it  may  be  desirable  to  thin  the 
seedlings,  as  any  approach  to  a  drawn,  weakly  condition  must  be 
most  carefully  avoided  from  the  first. 
A  well-dug  but  moderately  firm  soil,  enriched  by  a  liberal 
dressing  of  old  farmyard  manure  some  time  previous  to  planting, 
is  the  most  suitable  for  producing  strong  plants,  but  a  slight 
additional  dressing  of  superphosphate  (about  half  an  ounce  to  the 
square  yard),  applied  in  December  or  January  when  the  weather 
is  open,  has  resulted  in  the  production  of  finer  trusses  and  flowers 
than  where  this  was  omitted.  We  have  also  thought  that  the 
colours  have  been  both  richer  and  clearer  where  this  mineral 
manure  has  been  used.  Without  the  farmyard  manure  double  the 
quantity  of  artificial  has  not  produced  quite  the  same  effect,  except 
in  cases  where  the  soil  was  fairly  rich  from  the  residue  of  manure 
left  from  previous  crops.  Nitrate  of  soda  appears  to  be  too 
stimulating  for  Sweet  Williams,  for  though  tried  at  various  times 
and  in  different  quantities  the  results  were  not  so  satisfactory  as 
where  the  plants  were  allowed  to  make  a  more  natural  and  sturdy 
growth.  If  once  they  become  “  drawn  ”  they  are  comparatively 
useless. 
Arabis  albida. 
The  early  flowering  pure  white  Arabis  is  most  valuable  for  an 
edging  to  large  borders,  and  we  have  raised  many  thousands  from 
seed  sown  in  late  spring  or  early  summer  which  produced  excellent 
plants,  that  were  flowering  profusely  by  the  end  of  the  following 
February.  So  vigorously  do  the  plants  grow  in  oar  soil  and  under 
the  particular  treatment  tried,  that  several  friends  well  versed  in 
hardy  plants  have  failed  to  recognise  this  as  the  ordinary  Arabis 
albida  when  it  is  not  in  flower.  The  leaves  are  considerably  larger 
than  the  usual  type,  the  plants  forming  cushion- like  tufts  about  a 
foot  in  diameter  and  the  flowers  large,  and  produced  on  stout  sterns 
quite  clear  of  the  foliage.  At  the  present  time  (February  24th) 
some  of  these  are  flowering  most  abundantly,  and  we  have  counted 
as  many  as  150  spikes  on  one  plant. 
The  seed  has  been  sown  at  various  times,  from  April  until  early 
August,  and  in  fine  autumns  good  plants  have  been  secured  from 
the  later  sowing  for  flowering  in  the  following  year ;  but  when  the 
time  can  be  devoted  to  “  pricking  ”  out  the  seedlings  as  soon  as 
they  are  ready,  the  April  sowing  gives  the  best  results.  This  also 
enables  the  young  plants  to  recover  themselves  before  the  heat  of 
summer  is  upon  them — an  important  matter,  for  though  this  plant 
will  grow  and  thrive  upon  rockeries,  yet  in  the  young  state  a  dry 
situation  or  soil  seems  to  be  positively  injurious.  Upon  the  edge 
of  a  raised  border  the  plants  grow  admirably,  extending  to  the 
path  level,  as  while  being  moist  and  cool  ixcessive  rain  can  readily 
escape.  Superphosphate  has  a  surprising  effect  upon  this  plant 
when  used  only  at  the  rate  of  half  an  ounce  per  square  yard,  and 
after  trying  it  several  times  upon  plants,  in  contrast  with  others 
that  received  nothing  in  the  shape  of  manure,  we  always  employ  it 
now. — A  Countryman. 
(To  be  continued .) 
CHEMISTRY  IN  THE  GARDEN. 
( Continued  from  page  90.) 
Having  in  the  previous  articles  briefly  described  the  elements 
found  in  plants,  let  us  now  turn  our  attention  to  the  substance 
known  as  soil.  In  considering  soil  we  shall  find  it  necessary  to 
turn  on  side  lights  from  other  sciences,  for  the  purpose  of  giving 
more  illuminating  power  to  our  thoughts  on  its  chemistry. 
The  Origin  of  Soils. 
Astronomers  tell  us  that  millions  of  years  ago  our  earth  existed 
in  space  as  a  mass  of  glowing  gas.  Gradually  this  gas  parted  with 
some  of  its  heat  by  radiation,  and  as  the  temperature  fell  some 
of  the  substances  which  were  in  the  gaseous  state  condensed,  and 
became  liquids  similar  to  molten  lava.  On  further  cooling  the 
liquids  became  solids,  and  so  formed  the  primary  rocks  of  the 
earth. 
After  the  first  rocks  were  formed,  the  earth  was  no  doubt  so  hot 
as  to  make  it  impossible  for  water  to  exist,  except  as  watery  vapour 
(steam)  in  the  atmosphere  ;  but  as  the  temperature  of  the  rocks 
gradually  decreased  the  vapour  condensed  into  water  and  descended 
to  form  rivers,  seas,  and  oceans.  There  are  still  some  gases  left 
surrounding  our  earth— namely,  those  which  constitute  our  atmo¬ 
sphere  ;  but  any  of  these  can  be  made  to  assume  a  liquid,  and  even 
a  solid  form,  by  subjecting  them  to  a  very  low  temperature.  The 
primary  rocks  consisted  chiefly  of  granites,  syenites,  and  basaltic 
rocks,  and  when  first  formed  were  of  a  more  or  less  crystalline 
character.  Our  object,  however,  does  not  lie  so  much  with  the 
geology  of  the  rocks  as  with  their  chemistry,  so  before  proceeding 
we  will  give  the  chief  constituents  of  which  they  are  composed. 
The  granite  rocks  generally  con  istof  the  three  following  substances 
— quartz,  felspar,  and  mica. 
Quartz  consists  of  but  two  elements  —  namely,  silicon  and 
oxygen.  By  the  decay  of  the  granite  rocks  the  quartz  would  be 
liberated  as  grains  of  silica  or  sand. 
Felspar  is  composed  principally  of  silicates  of  alumina  which 
are  present  in  chemical  combination  either  with  potash,  soda,  or 
lime.  There  are,  however,  nearly  always  traces  of  magnesia,  oxide 
of  iron,  and  phosphoric  acid  also  present. 
Mica  is  not  unlike  felspar  in  composition.  It  consists  chiefly 
of  silicates  of  alumina  in  combination  with  magnesia  or  potash. 
There  are  large  quantities  of  oxide  of  iron  also  present  ;  but  soda, 
lime,  and  phosphoric  acid  are  entirely  absent. 
Syenite  is  a  variety  of  granite,  in  which  there  are  but  traces 
of  quartz  ;  and  the  mica  is  rep'aced  by  hornblende. 
Hornblende  consists  principally  of  silica,  iron  and  lime, 
together  with  smaller  quantities  of  alumina,  potash,  soda,  and 
phosphoric  acid. 
Basalt  is  a  dense  heavy  dark  coloured  rock,  consisting  either  of 
a  mixture  of  felspar  and  hornblende,  or  felspar  and  augite  ;  the 
last  named  being  a  substance  formed  by  the  union  of  silica  with 
magnesia. 
Seeing  what  very  important  substances  felspar,  mica,  and 
hornblende  are  in  the  composition  of  rocks,  we  think  it  advisable  to 
give  the  chemical  composition  of  the  three  minerals  just  named  : — 
Analysis  of  Minerals. 
Felspar. 
Mica. 
Hornblen 
Silica  . 
...  65-72  ... 
...  4(I'3G 
...  43-45 
Alumina  ... 
...  18-57  ... 
...  36-80  ... 
...  652 
Potash  . 
...  12-32  ... 
...  9-22  ... 
...  2-86 
Soda"  . 
...  1-25  ... 
...  none  ... 
...  3-27 
Lime  . 
...  0-34  ... 
...  none  ... 
...  10-25 
Magnesia . 
...  o-io  ... 
...  3  09  ... 
...  3'56 
Iron  Oxide 
none  ... 
...  4-53  -7.. 
...  29-98 
Phosphoric  Acid  ... 
...  1-70  ... 
...  none  ... 
...  0-11 
100-00 
100-00 
100  00 
These  analyses  show  us  what  a  large  quantity  of  silica  and 
alumina  there  is  present  in  the  minerals,  and  also  what  a  large 
amount  of  iron  oxide  hornblende  contains.  The  large  quantities 
of  potash  in  felspar  and  mica,  and  the  10  per  cent,  of  lime  in  horp- 
blende  is  also  very  noticeable,  showing  ua  that  the  first  two  named 
