336 
JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER. 
April  18,  1901. 
diluting  to  4  gallons  with  hot  water  and  applying  when  cool  enough 
(90°  to  100°).  Syringe  moderately  in  the  morning  and  on  fine 
afternoons,  always  early  enough  to  allow  the  foliage  to  become  fairly 
dry  before  nightfall.  Disbud  gradually,  and  rub  off  all  small  and  badly 
placed  fruit  as  soon  as  the  most  promising  show  signs  of  taking  the  lead. 
Ventilate  freely  on  all  favourable  occasions,  and  close  early  with  a  view 
of  husbanding  sun  heat,  but  avoid  a  close,  vitiated  atmosphere, 
admitting  a  little  air  constantly  to  prevent  it. 
Late  Houses. — Though  the  trees  in  these  are  rather  unusually 
forward  there  is  no  great  disadvantage  where  they  are  provided  with 
means  of  excluding  frost,  as  the  ripening  can  be  retarded  by  free 
ventilation  through  the  summer.  Ventilate  freely,  but  keep  safe  from 
frost.  During  the  flowering  and  afterwards  a  temperature  of  50°  should 
be  maintained  by  day,  keeping  it  at  that  with  a  little  gentle  circulation 
of  air,  turning  off  the  heat  early  in  the  afternoon,  so  as  to  allow  the 
pipes  to  cool  before  night,  and  the  temperature  falling  to  its  night 
minimum  of  40°  to  45°,  which  is  quite  safe,  and  ought  to  be  secured 
with  a  little  air  to  prevent  the  deposition  of  moisture  through  the  night 
on  the  flowers.  Artificial  fertilisation  should  be  resorted  to,  but  the 
best  security  for  setting  are  perfectly  developed  blossoms,  and  a  genial, 
well  aerated  atmosphere. 
All  correspondence  relating  to  editorial  matters  should  be  directed 
to  “The  Editor,”  12,  Mitre  Court  Chambers,  Fleet  Street, 
Xaondon,  E.c.  It  is  requested  that  no  one  will  write  privately 
to  any  of  our  correspondents,  seeking  information  on  matters 
discussed  in  this  Journal,  as  doing  so  subjects  them  to  unjustifiable 
trouble  and  expense. 
Carpet  Bedding  Design  (P.  B.). — You  will  find  a  goodly  selection, 
with  full  descriptions  for  the  filling  of  the  beds,  in  Cole’s  “  Royal  Parks 
and  Gardens  of  London,”  price  2s.  6d.  from  this  office.  You  might  also 
write  to  Messrs.  Cannell  &  Sons,  Swanley,  and  Messrs.  Toogood  &  Sons, 
Southampton,  who,  we  believe,  publish  little  booklets  of  designs  at  a 
few  pence  each. 
Crossing  Frimulas  (A.  G.  Hookings). — Mr.  Hookings  writes  to  us  as 
follows  “  I  was  much  interested  in  the  article  written  on  Primula 
Kewensis  and  Primula  obconica,  which  appeared  in  your  Journal  on 
March  the  8th,  1900,  signed  by  ‘  Scrutator.’  I  enclose  a  few  blooms  of 
Primula  stellata  crossed  with  Primula  obconica.  The  plant  has  the 
habit  of  Primula  stellata,  Primula  obconica  being  the  pollen  parent. 
I  shall  feel  obliged  if  you  will  give  me  your  opinion  of  them  through 
your  valuable  Journal.”  In  reply  to  our  correspondent  we  can  only 
say  that  there  seems  little  or  no  appearance  of  any  real  cross  having 
been  effected.  Had  Primula  obconica  been  the  seed  parent,  then  we 
would  have  said  at  once  that  the  male  or  pollen  plant — which,  of  course, 
would  thus  have  been  P.  stellata — had  been  entirely  prepotent,  and 
had  had  all  the  influence.  It  is  doubtful  in  your  case  whether  the 
pollen  from  the  P.  obconica  blooms  ever  fertilised  the  flowers  of 
P.  stellata  at  all.  The  yellow  disc  or  eye  of  the  flowers  you  sent  was 
very  bright  and  deep,  but  otherwise  there  was  not  the  slightest  clue  to 
any  cross  having  been  made.  Have  any  others  of  our  readers  tried  this 
cross  ;  if  so,  would  they  let  Mr.  Hookings  know  the  results  p  At  any 
rate,  have  another  try ;  and  why  not  try  to  cross  with  the  Sieboldi 
varieties  ? 
Heating  Power  of  Saddle  Boiler  (Henri).—' The  boiler,  6  feet  long 
from  doors  to  furnace  end,  18  inches  wide,  and  about  same  in  depth, 
being  an  ordinary  saddle,  will  have  actual  heating  power  of  1000  feet 
of  4-inch  pipe,  but  allowing  for  depreciation  through  sooty  deposit  this 
will  be  reduced  about  one-fourth,  or  to  750  feet.  If,  however,  the 
boiler  has  a  waterway  end,  with  flue  openings  at  sides,  it  will  have  a 
heating  power  of  1600  feet  of  4-inch  piping,  and  allowing  a  fourth  for 
depreciation  through  sooty  deposit,  should  heat  1200  feet,  the  flues 
being  kept  clean  and  good  stoking  practised.  Possibly  the  best  way  to 
take  off  the  coating  of  lime  in  the  boiler  would  be  to  throw  into  the 
tank  or  boiler  2  ozs.  of  caustic  soda  to  every  100  gallons  of  water ; 
though  an  excess  of  caustic  soda  will  not  injure  the  boiler  in  any  way, 
yet  it  is  not  advisable  to  use  more  than  3  ozs.  of  caustio  soda  to  every 
100  gallons  of  water  thrown  into  the  boiler.  To  prevent  incrustation 
the  water  should  be  softened,  £  lb.  of  caustio  lime  made  into  milk  in 
a  pailful  of  water  and  thrown  into  400  gallons  of  water ;  the  oaustic 
lime  neutralises  the  carbonic  acid,  removes  the  solvent,  and  becoming 
at  the  same  time  carbonate  of  lime,  is  preoipitated  with  that  originally 
in  solution.  Hard  water  may  also  be  softened  by  using  a  pound  of 
anti-calcaire  to  250  gallons  of  water,  or  a  quarter  pound  of  washing 
soda,  dissolved  in  hot  water,  to  36  gallons  of  water,  allowing  in  either 
case  to  stand  twenty-four  hours,  when  it  will  be  soft.  When  the  water 
is  used  care  should  be  taken  not  to  disturb  the  sediment. 
Oxera  pulchella  (A.  M.). — Unfortunately  we  have  not  the  full  address 
of  “  R.  H.,”  who  wrote  the  article  you  refer  to.  We  shall  pursue  our  in¬ 
quiries.  Have  you  written  to  one  or  two  of  the  large  plant  nurserymen  ? 
Collection  of  Vegetables  (Essex). — As  a  rule  in  large  societies,  or 
where  the  exhibitors  are  intelligent,  experienced  gardeners,  and  the 
best  trained  judges  are  expected  to  judge,  such  wording  as  “For  the 
best  collection  of  vegetables  ”  is  held  sufficient.  The  case  is  very 
different  when  cottagers’  collections  of  vegetables  are  considered.  It  is 
much  the  wiser  plan  to  specify  a  certain  number  of  vegetables,  and  even 
to  name  them  (in  order  of  importance)  in  the  schedule.  Suoh  a  oourse 
then  greatly  relieves  the  judges  from  suspicions  of  favouritism  or  other 
unpleasantness  when  the  show  comes  off.  Better  be  explicit  than  run  the 
risk  of  any  bickerings,  which  generally  act  unfavourably  on  societies. 
Soaking  Peis  in  Petroleum  before  Sowing  (J.  W.  M.). — Paraffin  oil 
may  safely  be  used  for  dressing  Peas  and  Beans  before  sowing,  we 
having  practised  it  for  many  years  as  a  safeguard  against  mice  and  rats 
taking  them  ;  but,  instead  of  soaking  the  Peas,  we  place  the  quantity  to 
be  sown  at  one  time  of  the  respective  variety  in  a  flower  pot  sufficiently 
large  with  the  hole  corked,  and  sprinkle  on  them  the  petroleum  in 
amount  calculated  to  moisten  them  all  over,  this  being  effected  by 
shaking  the  Peas  in  the  pot  by  an  upward  and  turnover  movement, 
until  coated  with  the  oil  all  over  the  skin,  any  exoess  of  oil  being  run 
off  by  holding  the  hand  over  the  seed  and  partly  inverting  the  pot. 
Suoh  practice  we  have  found  very  successful,  the  seed  being  sown  at 
once,  not  any  pests  interfering  with  the  seed,  and  this  is  not  prejudiced 
by  the  dressing.  It  is  not  advisable  to  use  petroleum  in  the  raw  state 
for  watering  Peas  or  other  crops  after  the  seed  is  sown  and  the  plants 
growing,  as  the  oil  itself  is  injurious  to  the  growths  and  prejudices  the 
soil  as  a  rooting  and  feeding  medium.  If  used,  it  should  be  in  the  form 
of  emulsion,  which  may  be  purchased  in  the  form  known  as  petroleum 
or  paraffin  softsoap,  or  made  as  follows  for  use  as  required.  Dissolve 
1£  lb.  of  softsoap  by  boiling  in  a  gallon  of  water,  and  when  dissolved 
remove  from  the  fire  for  safety,  and  add  half  pint  of  petroleum,  stirring 
briskly  with  a  switch  made  of  twigs,  or  part  of  an  old  birch  broom, 
until  thoroughly  amalgamated,  and  dilute  with  hot  water  to  eight  gallons 
for  use,  applying  when  cool  enough,  either  by  means  of  a  syringe  or 
rose  watering  pot.  At  this  strength  it  may  safely  be  used  on  Peas  or 
other  crops  with  smooth  leaves,  preferably  in  the  early  evening  as 
preventive  of  predatory  pests  attacks.  For  use  on  fruit  trees  and  other 
crops  it  should  be  diluted  to  twelve  gallons,  and  is  very  effective  against 
aphides,  red  spider,  &c. 
Heating  Lean-to  Plant  House  in  Three  Compartments  (W.  R.  R.)- — 
The  most  simple  and  economical  mode  of  heating  the  structures  would 
be  to  have  the  stokehole  and  boiler  fixed  at  the  point  in  the  boiler-shed 
near  the  first  partition,  but  so  that  the  flow  and  return  pipes  would  be 
in  the  stove,  and  taken  across  the  end  of  it  alongside  the  partition 
beneath  the  floor  level.  After  crossing  the  front  (and  we  presume  only 
pathway,  there  being  a  shelf  in  front  3  feet  wide,  and  then  a  pathway 
of  about  that  width,  leaving  4  feet  for  back  staging)  the  flow  pip® 
should  branch  to  the  right  and  left  by  means  of  a  T  piece,  and  on  the 
stove  side  of  this  a  screw  valve  should  be  affixed.  A  two-branch  pipe 
should  adjoin  the  valve,  and  two  rows  of  4-inch  pipes  taken  along  the 
front  of  the  stove  beneath  the  shelf  and  across  the  end  to  the  doorway, 
where  on  each,  at  the  point  just  before  the  return  is  made  and  on  the 
syphon,  should  be  an  air-pipe,  the  pipes  continuing  back  beneath  the 
other  or  flow  pipes  to  where  these  branch,  and  there  the  small  returns 
are  joined  to  the  return  pipe  by  a  two-branch  pipe.  The  stove  will  thus 
have  two  flows  and  two  returns  along  the  front  and  part  of  one  end,  and 
also  the  main  flow  and  return  pipes  at  the  other,  the  pipes  being  in  a 
flue  with  iron  grating  over.  The  other  branch  from  the  main  flow 
should  be  taken  through  into  the  middle  compartment,  and  a  screw 
valve  affixed  just  within,  then  a  two-branch  pipe,  two  pipes  along  the 
front  to  near  the  end,  there  fixing  a  two-branch  pipe,  and  next  this  an 
H  piece,  which  has  two  throttle  valves.  The  return  will  thus  be  made 
by  a  single  pipe.  To  heat  the  greenhouse  a  flow  and  return  pipe  along 
the  front  will  suffice,  continuing  these  from  the  H  piece,  and  with 
proper  iodine,  so  as  to  have  the  highest  point  at  the  further  end  of  the 
greenhouse  oompartment,  and  there  an  air  pipe  on  the  syphon.  By  this 
arrangement  the  greenhouse  can  be  heated  by  opening  the  H  valves,  or 
closing  them  when  not  required,  thus  saving  a  flow  and  return  pipe  the 
whole  length  of  the  intermediate  compartment.  To  heat  the  pits  you 
will  require  to  take  forward  a  flow  from  the  main  flow  pipe,  and  have  a 
valve,  so  as  to  regulate  the  heat  as  desired,  a  4-inch  pipe  being  mostly 
sufficient  along  the  front.  There  will  be  about  100  feet  of  4-inoh  piping 
in  the  stove,  36  feet  in  the  intermediate  house,  and  32  feet  in  the 
greenhouse,  whioh,  with  between  40  and  50  feet  in  the  pit,  will  aggregate 
under  250  feet  of  4-inch  piping,  and  would  be  satisfactorily  heated  by  a 
24  inches  long  saddle  boiler  with  waterway  and  flue  openings  at  sides, 
this  having  a  calculated  heating  power  of  350  feet  in  4-inch  piping, 
though  it  is  always  better  to  have  a  boiler  above  rather  than  below  its 
heating  power,  therefore  advise  one  of  30  inches  length,  heating  450  feet 
of  4-inch  piping.  As  you  require  a  somewhat  high  temperature  in  the 
stove,  it  would  be  advisable  to  have  a  flow  and  return  pipe  at  the  back 
beneath  the  staging.  By  the  foregoing  arrangement  you  would  be  able 
to  heat  all  the  structures  separately  or  together,  excepting  the  inter¬ 
mediate  house,  through  which  the  hot  water  must  pass  to  heat  the 
greenhouse.  It  is  desirable  to  have  valves  on  both  the  flow  and  return 
pipes,  as  when  not  on  the  latter  the  heat  is  liable  to  back-up  them, 
though  the  flow  valves  are  closed. 
