Nov.  1,  1895,]  Supplement  to  the  ^'Tropical  Agriculturists 
363 
conclusinns  resulted  from  enquiries  into  the  re- 
lation of  both  these  sources  of  nitrogen  with 
plant  life,  till  fresh  research  in  a new  direction 
altogether,  helped  to  reconcile  the  apparently 
contradictory  results. 
(1.)  As  regards  Atmospheric  Nitrogen. — Some 
fifty  years  ago,  Boussingault,  as  well  as  Lawes, 
Gilbert,  and  Pugh  conclusively  proved  that  plants 
do  not  absorb  free  nitrogen  from  the  air  through 
their  leaves.  And  yet  Ville  has  brought  forward 
no  less  conclusive  evidence  to  prove  that  in  some 
way  unknown  small  quantities  of  nitrogen  always 
find  their  way  from  the  atmosphere  into  a vigorous 
plant  (irrespective  of  the  ammonia  and  nitric 
acid  that  might  be  derived  from  the  atmosphere). 
(2.)  As  regards  Soil  Nitrogen. — We  are  told  that 
Liebig  declared  that  cultivable  soils  have  quite 
enough  of  nitrogen  for  agricultural  purposes — 
left  by  previous  generations  of  plants — and 
advised  that  the  mineral  salts  carried  away  by 
plants  should  be  returned  to  the  soil.  But  it 
was  found  on  the  contrary  that  plants  could  not 
do  without  nitrogenous  manures,  and  that  the 
addition  of  stable  manure  gave  vigour  to  plants 
and  seemed  to  vivify  the.se  very  nitrogen  com- 
pounds previously  pre.sent  in  the  soil. 
Prince  Krapotkin  then  goes  on  to  show  how 
experimentalist.s  gradually  came  to  see  that  che- 
mical experiments  carried  on  in  Laboratories  were 
insufficient  to  explain  away  the  apparent  contra- 
dictions referred  to  above,  and  to  account  for  the 
true  relationship  between  the  plant  and  the 
nitrogen  found  • in  the  soil  and  the  air , how, 
while  we  are  more  and  more  persuaded  that 
chemical  processes  that  are  going  on  within 
are  complex  and  unstable  compounds  are  the 
real  basis  of  life,  we  have  also  come  to  know 
that  the  seat  of  these  processes  must  be  looked 
for  in  the  infinitesimal  component  parts  of  the 
organism  and  the  microscopical  inhabitants  of  its 
organs. 
It  has  been  proved  to  conviction  that  the 
progressive  increase  in  the  perce.itage  of  nitrogen 
in  soil  left  uncultivated  is  due  to  the  lower 
fungi  and  micro-organisms  which  develope  in 
prodigious  quantities  in  decaying  vegetable  matter. 
Neither  the  nitrogen  shut  up  in  vegetable  mould 
or  in  the  form  of  insoluble  ammoniacal  salts  so 
easily  formed  in  a clayey  soil  is  of  any  direct 
avail  to  plants.  It  is  now  known  not  only  that 
a “ living  ferment’’  is  necessary  for  the  produc- 
tion of  nitric  acid  and  nitrates  in  the  soil,  but 
also  that  the  process  of  converting  ammonia  into 
nitric  acid  is  performed  by  special  microbes,  and 
that  two  different  bacteria  are  requiied  to  accom- 
plish the  full  process — one  to  deco  upose  ammonia 
and  transform  it  into  water  and  nitrous  acid,  the 
other  to  further  oxidise  this  acid  and  convert  it 
into  nitric  acid.  Without  these  two  microbes, 
which  are  continually  preparing  tresh  nitric  acid 
in  the  soil,  while  the  j)revious  stocks  of  it  are 
washed  into  the  subsoil,  agriculture  would  be  in 
a precarious  state.  In  the  enquriy  into  the  re- 
lation between  plants  and  free  atmospheric 
nitrogen,  it  was  first  discovered  (by  Wilfarth  and 
llellriegel)  that  the  roots  of  papilionaceous 
leguminos;e — which  striking  showed  an  apparent 
independence  as  regards  soil  nitrogen — were 
found  in  fertile  soils  to  be  covered  with  nodules 
originated  from  agglomerations  of  bacteria 
(ijf.  radicicola)  which  have  a sort  of  symbiotic 
association  with  the  plants,  It  has  heca  further 
demonstrated  (by  Schlosing,  jr.  and  Laurent)  that 
various  mosses  and  especially  algae  {Conferva;, 
Oscellarue  Nitrseckea)  which  usually  develope 
on  the  surface  of  the  soil  also  absorb  nitrogen 
from  the  air.  But  legumiuoaes  are  not  the  only 
higher  plants  that  can  utilize  atmospheric  nitrogen 
by  the  aid  of  bacteria.  Eknngnus  angustifolia  (a 
garden  shrub  nearly  allied  to  the  laiiral  tribe) 
has  also  been  found  to  harbour  the  bacteria  that 
utilize  atmospheric  nitrogen,  though  different 
from  B.  radicicola.  Indeed,  it  appears  that  each 
species  of  leguminosae  has  its  own  bacteria 
e.specially  appropriate  for  entering  into  a mutual 
benefit  association. 
These  discoveries,  to  quote  Prince  lirapotkin’s 
own  words  “ have  solved  enigmas  of  long  standing, 
and  to  the  practical  agriculturist  they  promise 
a new  method  for  improving  the  soil  by  watering 
it  with  liquids  containing  the  necessary  microbes. 
Once  inoculated  into  the  soil  the  nitromonade 
(or  nitrosomonas)  of  the  soil  and  the  Bacteria 
radicicola  in  the  root  nodule  will  continue  their 
'^'ork The  fact  that  the  nitromonade  though 
devoid  of  chlorophyll  is  capable  of  making  the 
synthesis  of  organic  compounds  out  of  purely 
mineral  salts  is  of  immense  importance  in  the 
economy  of  nature.” 
It  has  been  proved  that  the  beech  can  only 
thrive  when  a mantle  of  mycorhiza  fungi  enve- 
lope its  roots,  and  while  obtaining  their  nutriment 
from  the  soil  yield  part  of  it  to  the  roots 
of  the  tree.  The  same  has  been  found  true  in 
the  case  of  the  pine. 
In  conclusion,  to  quote  Prince  Krapotkin  again, 
“ all  these  are  evidently  but  separate  instances  of  a 
much  more  general  fact,  which  only  recently 
became  known  under  the  general  name  of  symbio- 
sis, and  appears  to  have  an  immense  signification 
in  nature.  Higher  plants  depend  upon  lower 
fungi  and  bacteria  for  the  supply  of  that  impor- 
tant part  of  their  tissue,  nitrogen.  Lower  fungi 
associate  with  unicellular  algm  to  form  that  great 
division  of  the  vegetable  world  the  lichens.  More 
than  a hundred  different  species  of  algm  are 
already  known  to  live  in  the  tissues  and  the  cells 
of  animals,  and  to  render  each  other  mutual 
services.  And  so  on,  associations  of  high  and  low 
organisms  are  discovered  every  day;  and  when 
their  coeditions  of  life  are  more  closely'  examined, 
the  whole  cy'cle  of  life  changes  its  aspect  and 
requires  a much  deeper  signification.’’ 
LAWS  OF  CEYLON  RELATING  TO 
AGRICULTURE. 
Chapter  X. — ( Continued. J 
6.  Provided,  however,  that  nothing  in  sections 
3, 4 and  o of  this  chapter  shall  apply  to— 
( ((■)  Any  channel,  watercourse  or  ela  which 
has  been  or  may  hereafter  be  cut,  opened,  or 
constructed  for  irrigation  purpo.ses  within  a 
period  of  not  less  than  one  y'ear  after  such  land 
or  premises  or  portions  thereof  shall  have  been 
cleared  and  drained  for  cultivation,  except  in  so 
far  as  such  channel,  watercourse,  or  ela  may  be 
so  blocked  or  obstructed  by  reason  of  any  further 
and  additional  clearing  carried  on,  or  any  further 
and  additional  drains  opened,  on  such  land  or 
premises  or  portions  thereof  after  such  channel, 
watercourse,  or  ela  has  been  so  cut,  opened,  or 
constructed  as  aforesaid  5 or— 
