March  i,  1893.]  THE  TROPICAL  AGRICULTURIST. 
ELEMENTS  OF  AGRICULTURE.* 
ALL  ABOUT  SOILS  AMD  MANURE  : THE  TEA  TRADE  AND  SOIL. 
This  is  a book  which  should  be  valuable  to  all 
who  get  thfir  living  by  the  cultivation  cf  the 
soil.  This,  of  course,  is  practised  in  the  best 
and  most  scientific  manner  in  general  “farming” 
and  gardening  ; but  the  principUs  are  the  same 
everywhere,  so  far  as  they  apply  to  the  mechani- 
cal (geological)  and  chemical  nature  of  the  soil,  its 
fitness  for  any  particular  product,  its  preservation 
and  fertilization.  This  book  < xpLins  the  science  of 
til  age  in  language  brought  down  to  the  level 
of  the  most  ordinary  intelligence,  while  it  teaches 
al!  the  6lemen!ary  fao's  of  the  geology  of  the  earth’s 
surfaoe,  of  agricultural  chemistry,  ihe  practical 
cultivation  of  sou,  as  well  as  (for  the  farmer  in 
Europe)  a 1 about  the  live  and  dead  stock  he  neoessa- 
rily  has  to  employ  ; and  also  how  to  know,  and  to 
treat,  the  insect  and  fungus  pests  that  attack 
his  orops.  For  the  Ceylon  Planter  Parts  I.  end 
II.,  wbioh  deal  with  the  “ Soil  ” and  the 
“ Plant,”  are  wholly  interesting,  and  should 
be  well  understood  by  all  who  lay  claim  to  a 
liberal  education.  The  book  has  over  400 
pages,  is  profusely  illustrated,  and  provided 
with  a good  “Index,”  by  means  of  which  reference 
oan  be  instantaneously  made  to  any  of  the  many 
subjects  it  deals  with. 
Some  of  these  are,  in  Part  I.,  “Origin  and  pro- 
perties of  soils,  composition  and  c assification, 
sources  of  loss  and  gain,  moisture  and  manures;” 
while  in  Part  II.,  we  are  instructed  regarding  “Seeds 
and  their  germination,  the  selection,  (unctions  and 
cultivation  of  seeds  and  plants,  weeds,  fungus  and 
inseot  pests.”  It  may  be  useful  to  notioe  a few 
of  the  less  ins  here  taught : — 
“ All  orops  oan  be  traced  back  to  two  primary 
sources,  the  soil  and  the  atmosphere.  The  same 
is  true  of  animals  and  their  products. 
“ The  soil  can  be  regarded  as  derived  from  the 
sub-soil  ; air,  moisture,  temperature,  plants  and 
animals  being  the  ohief  agenis  in  efbofcmg  the  change. 
“Humus  (organic  matter).  After  having  thoroughly 
dried  a portion  of  soil  of  its  moisture,  weigh  1 lb, 
of  it,  and  burn  it  on  a red  hot  iron  plate  or  old 
fryiDg-pan : a strong  smelliDg  smoke  will  arise. 
After  the  smoke  has  ceased  to  appear  let  it  cool. 
Weigh,  and  the  loss  was  the  humus  (the  decaying 
remains  of  plants  and  of  animals.) 
•'Humus  is  of  value  beaause  the  final  products 
of  its  decomposition— chit  fly  carbonic  acid,  ammonia 
and  water — administer  to  the  food  requirements  of 
plants.  The  quantity  of  humus  in  cultivated  soils 
usually  ranges  from  2 to  9 per  cent,  and  within 
these  limits  the  soil  will  be  the  more  fertile  the 
more  humus  it  oontains.  It  is  possible,  however, 
for  a soil  to  oontain  too  much  decaying  organio 
matter  ; this  is  the  case  with  peaty  soils  and 
boggy  moorlands. 
“Put  another  weighed  quantity  of  the  dried  and 
powdered  soil  into  a bottle  of  rain  water — shake  it 
well,  and  let  it  stand  a day  or  so.  Then  carefully 
pour  off  the  clear  liqui  1 into  a saucer,  or  basin. 
The  loss  in  weight,  (after  again  being  dried)  re- 
presents the  soluble  ingredients,  and  these  may  be 
obtained  by  evaporating  the  water  in  the  basin. 
It  is  the  soluble  parts  of  the  soil  only  that  plants 
feed  on. 
“When  water  that  has  trickled  through  a soil 
flows  away  from  it,  some  of  the  soluble  matter — 
and  in  some  oases  a considerable  portion  of  it — 
may  be  oarried  away  in  the  water. 
* “ Elements  of  Apiculture .” — A Text  Book  pre- 
pared und  r the  authority  of  the  Royal  Agricul- 
tural Sooiely  or  Eogla.  d,  by  W.  Freain,  LL.p.  3id 
Edition.  2s  fid.  John  Murray,  Loudon. 
U 
561 
"The  constituent  parts  ofasoil  are  for  ever  changing. 
— Crops  are  continually  carrying  away  certain 
ingredients,  whilst  the  fine  earth  of  the  soil  is  as 
constantly  being  added  to  by  the  decomposition,  or 
deoay  of  the  stony  fragments  which  the  soil  con- 
tains, In  addition,  the  rain  which  falls  upon  the 
land  brings  with  it  from  the  atmosphere  certain 
substances  which  are  of  muoh  importance  in  culti- 
vated soils.” 
Here  the  reviewer  may  stop  to  add  that  ground 
aqueous  rooks  is  coming  largely  into  use  in  England 
as  manure. 
“ For  many  years  past  the  reduction  of  rocks  for 
manure  has  Inen  carried  on  in  a small  way  by  a 
system  of  calcining,  thus  softening  the  rook,  and 
afterwards  reduoing  to  powder  by  a primitive 
method  of  stamping.  In  a German  standard  work 
on  vegetarianism  I read : ‘ With  Hensal’s  rock- 
flour  as  manure  there  has  been  obtained  for  years 
past  the  best  and  soundest  crops  without  any 
addition  whatever  of  nitrogenous  substances.’— 
English  Mechanic." 
Tne  cla- sifioation  of  soil  into  sandy,  loamy, 
olayey,  clay-loamy  and  strong  olay  is  then  shown 
to  be  a simple  process.  “Experience  proves  that  a 
soil  is  best  adapted  for  cultivation  when  it  oon- 
tains of — 
Sand  (siliceous  and  caloareous)  from  50  to  70  peroent 
Clay  . . , . 2d  to  30  ,, 
Pulverized  limestone  ..  5 to  1 0 ,, 
Humus  . . . . 5 to  10  „ 
“It  thus  contains  enough  sand  to  make  it  warm 
and  pervious  to  air  and  moisture ; enough  clay 
to  render  it  moist,  tenacious  and  conservative  of 
manures ; enough  limestone  to  furnish  caloareous 
material  and  to  decompose  organio  matter;  and 
lastly,  sufficient  humus  to  assist  in  supplying  the 
food  requirements  of  the  plants,  and  to  aid  in 
maintaining  the  oarbonio  aoid  in  the  interstitial 
air  of  the  soil. 
“Nitrogen,  phosphoric  acid,  potash  and  lime  are 
the  four  ingredients  that  are  liable  to  run  short 
in  a soil,  and  ihe  deficiency  of  which  has  to  be 
made  good  by  the  cultivator. 
Soil,  sustains  loss  in  the  orops  it  bears,  and  in  the 
drainage  water  oarrying  away  fine  earth  in  suspen- 
sion, and  iD  solution.  Experience  has  shown  that 
expulsion  of  soluble  salts  from  the  soil  takes  place 
most  freely  when  the  pereulation  of  moisture  is 
the  most  rapid,  so  that  a heavy  rainfall,  restricted 
to  a few  days,  does  far  more  harm  in  washing  a 
soil,  than  would  the  same  amount  of  rainfall 
spread  over  a month. 
“The  souroes  of  gain  to  soils  are  in  the  land 
itself,  in  the  atmosphere,  in  the  residues  of  orops, 
and  the  application  of  manures,  and  of  other 
dressings.” 
The  above  are  a few  of  theielementary,  but  useful, 
lessons  taught  and  fully  explained  in  the  early 
ohapters  of  this  book.  From  them  and  others  the 
thoughtful  reader  may  deduce  muoh  knowledge  and 
solve  problems  that  puzzle  him  in  practice. 
Thus,  near  old  oooly  lines  tea  will  seldom  grow, 
because  the  soil  has  been  “soured.”  We  read: — 
Soils  containing  too  much  organio  matters  become 
what  is  termed  ‘ sour  ’ owing  to  the  excess  of 
organio  acids.  Lime  by  combining  with  such  acids, 
renders  them  harmless.  ’ 
We  talk  (it  may  be  incidentally  remarked)  of  the 
tea  tree  being  a deep-feeder.  Of  oourse  the  roots 
wandering  down  into  the  sub-soil  are  in  search  of 
what  they  may  devour  ; but  this  oonsists  chiefly 
of  moisture  supporting  the  plant  through  droughts, 
though  when  suoh  long  whippy  roots  strike, 
or  find  a hole,  or  pooket  of  good  soil,  or  food 
they  develop  at  that  spot  a bunch  of  fibrous 
rootlets  to  absorb  the  nourishment,  Generally,  I 
