﻿AS 
  A 
  SOURCE 
  OF 
  THE 
  NITROGEN 
  FOUND 
  IN 
  PLANTS. 
  595 
  

  

  of 
  nitric 
  acid 
  does 
  ; 
  yet, 
  as 
  in 
  the 
  numbers 
  I 
  have 
  quoted, 
  the 
  weight 
  of 
  acid 
  

   exceeds 
  that 
  of 
  alkali 
  three 
  and 
  a-half 
  times, 
  it 
  appears 
  that, 
  so 
  far 
  as 
  we 
  have 
  

   quantitative 
  observations 
  on 
  the 
  matter 
  to 
  refer 
  to, 
  a 
  larger 
  amount 
  of 
  nitrogen 
  is 
  

   offered 
  to 
  plants 
  in 
  rain-water, 
  in 
  the 
  form 
  of 
  nitric 
  acid, 
  than 
  in 
  that 
  of 
  ammonia. 
  

  

  I 
  have 
  separated 
  the 
  question 
  of 
  the 
  occurrence 
  of 
  nitric 
  acid 
  in 
  rain-water, 
  

   from 
  that 
  of 
  its 
  development 
  in 
  the 
  atmosphere 
  by 
  oxidation, 
  and 
  by 
  electricity 
  ; 
  

   because 
  it 
  is 
  not 
  certain 
  that 
  the 
  whole 
  of 
  the 
  nitrates 
  found 
  in 
  rain-water 
  have 
  

   been 
  produced 
  by 
  a 
  process 
  like 
  that 
  of 
  nitrification, 
  or 
  by 
  the 
  action 
  of 
  lightning- 
  

   discharges 
  on 
  the 
  air. 
  Since 
  rain-water 
  is 
  found 
  to 
  contain 
  common 
  salt, 
  lime, 
  

   magnesia, 
  and 
  the 
  like, 
  which 
  have 
  been 
  raised 
  into 
  the 
  atmosphere 
  from 
  the 
  

   earth, 
  or 
  from 
  the 
  bodies 
  of 
  water 
  at 
  its 
  surface, 
  we 
  cannot 
  refuse 
  to 
  credit 
  that 
  

   nitre 
  may 
  be 
  elevated 
  in 
  the 
  same 
  way. 
  I 
  might 
  go 
  further, 
  for 
  attention 
  has 
  long 
  

   been 
  directed 
  to 
  the 
  fact, 
  that 
  there 
  is 
  a 
  marked 
  loss 
  during 
  the 
  evaporation 
  of 
  

   solutions 
  of 
  common 
  nitre, 
  in 
  consequence 
  of 
  that 
  salt, 
  although 
  not 
  volatile 
  in 
  

   the 
  dry 
  state, 
  undergoing 
  volatilisation 
  along 
  with 
  the 
  vapour 
  of 
  water. 
  This 
  

   is 
  a 
  secondary 
  point, 
  but 
  it 
  is 
  important, 
  as 
  shewing 
  that, 
  apart 
  altogether 
  from 
  

   oxidation, 
  and 
  from 
  thunder-storms, 
  there 
  is 
  a 
  source 
  from 
  which 
  the 
  atmosphere 
  

   everywhere 
  may 
  receive 
  compounds 
  of 
  nitric 
  acid. 
  

  

  Fourthly, 
  It 
  has 
  been 
  known 
  for 
  more 
  than 
  a 
  century, 
  that 
  many 
  springs 
  

   contain 
  nitrates. 
  

  

  Fifthly, 
  It 
  is 
  now 
  universally 
  admitted, 
  that 
  wherever 
  nitrogenous 
  vegetable 
  

   or 
  animal 
  matter 
  is 
  exposed 
  to 
  the 
  air 
  along 
  with 
  alkaline 
  bases, 
  ammonia 
  is 
  

   developed, 
  and 
  then 
  oxidised 
  into 
  nitric 
  acid, 
  which 
  combines 
  with 
  the 
  bases. 
  

   Now, 
  those 
  conditions 
  are 
  extensively 
  realised 
  all 
  over 
  the 
  globe, 
  both 
  in 
  culti- 
  

   vated 
  and 
  uncultivated 
  tracts 
  of 
  land; 
  and 
  in 
  the 
  warmer 
  regions 
  of 
  the 
  earth, 
  

   where 
  decomposition 
  proceeds 
  with 
  greatest 
  rapidity, 
  the 
  production 
  of 
  nitre 
  in 
  

   the 
  soil 
  is 
  constant 
  and 
  immense. 
  India 
  alone 
  furnishes 
  Great 
  Britain 
  with 
  all 
  

   the 
  nitre 
  needed 
  for 
  her 
  gunpowder. 
  

  

  Sixthly, 
  The 
  most 
  marked 
  nitrous 
  districts 
  of 
  India 
  are 
  celebrated 
  for 
  their 
  

   fertility, 
  provided 
  a 
  due 
  supply 
  of 
  water 
  is 
  furnished 
  to 
  them. 
  

  

  Seventhly, 
  The 
  alkaline 
  nitrates 
  dissolved 
  in 
  water, 
  and 
  not 
  employed 
  in 
  too 
  

   strong 
  solutions, 
  have 
  been 
  found 
  greatly 
  to 
  quicken 
  the 
  growth 
  of 
  plants 
  ; 
  and 
  the 
  

   nitrate 
  of 
  soda 
  which, 
  from 
  its 
  cheapness, 
  is 
  the 
  most 
  accessible, 
  is 
  daily 
  coming 
  

   into 
  greater 
  use 
  among 
  our 
  farmers. 
  In 
  the 
  current 
  number 
  of 
  the 
  Journal 
  of 
  the 
  

   Royal 
  Agricultural 
  Society,* 
  will 
  be 
  found 
  the 
  last 
  of 
  a 
  series 
  of 
  papers 
  on 
  this 
  sub- 
  

   ject, 
  in 
  which 
  the 
  virtues 
  of 
  nitrate 
  of 
  soda 
  in 
  increasing 
  the 
  amount 
  of 
  wheat 
  

   yielded 
  by 
  a 
  field 
  manured 
  with 
  it, 
  are 
  placed 
  by 
  Mr 
  Pusey 
  above 
  those 
  of 
  ammonia. 
  

  

  It 
  has 
  been 
  asserted, 
  indeed, 
  that 
  alkaline 
  nitrates 
  are 
  serviceable 
  to 
  plants 
  

   only 
  by 
  furnishing 
  them 
  with 
  alkalies 
  ; 
  but 
  I 
  know 
  not 
  by 
  what 
  arguments 
  it 
  is 
  

   proposed 
  to 
  defend 
  this 
  opinion. 
  It 
  is 
  at 
  variance 
  with 
  the 
  experience 
  of 
  farmers, 
  

   who 
  find 
  nitrate 
  of 
  soda, 
  as 
  Mr 
  Pusey 
  reports,! 
  a 
  powerful 
  fertiliser 
  where 
  common 
  

  

  * 
  Vol. 
  xiii., 
  Part 
  ii., 
  p. 
  366. 
  t 
  IUd 
  - 
  P- 
  349 
  - 
  

  

  VOL. 
  XX. 
  PART 
  IV. 
  7 
  Y 
  

  

  