﻿Artificial 
  and 
  Natural 
  Selection 
  809 
  

  

  exact 
  determination 
  of 
  three 
  hundred 
  thousand 
  

   polarization-values 
  of 
  beets 
  within 
  a 
  few 
  weeks. 
  

   Such 
  figures 
  give 
  the 
  richest 
  material 
  for 
  statis- 
  

   tical 
  studies, 
  and 
  at 
  once 
  indicate 
  the 
  best 
  roots, 
  

   while 
  they 
  enable 
  the 
  breeder 
  to 
  change 
  his 
  

   standard 
  in 
  accordance 
  with 
  the 
  results 
  at 
  any 
  

   time. 
  Furthermore 
  they 
  allow 
  the 
  mass 
  of 
  

   the 
  beets 
  to 
  be 
  divided 
  into 
  groups 
  of 
  dif- 
  

   ferent 
  quality, 
  and 
  to 
  produce, 
  besides 
  the 
  

   seeds 
  for 
  the 
  continuation 
  of 
  the 
  race, 
  a 
  first- 
  

   class 
  and 
  second-class 
  product 
  and 
  so 
  on. 
  In 
  

   the 
  factory 
  of 
  Messrs. 
  Kuhn 
  & 
  Co., 
  at 
  Naarden, 
  

   Holland, 
  the 
  grinding 
  machine 
  has 
  been 
  mark- 
  

   edly 
  improved, 
  so 
  as 
  to 
  tear 
  all 
  cell-walls 
  asun- 
  

   der, 
  open 
  all 
  cells, 
  and 
  secure 
  the 
  whole 
  of 
  the 
  

   sap 
  within 
  less 
  than 
  a 
  minute, 
  and 
  without 
  heat- 
  

   ing. 
  

  

  It 
  would 
  take 
  too 
  long 
  to 
  go 
  into 
  further 
  de- 
  

   tails, 
  or 
  to 
  describe 
  the 
  simultaneous 
  changes 
  

   that 
  have 
  been 
  applied 
  to 
  the 
  culture 
  of 
  the 
  

   elite 
  strains. 
  The 
  detailed 
  features 
  suffice 
  

   to 
  show 
  that 
  the 
  chief 
  care 
  of 
  the 
  breeder 
  in 
  this 
  

   case 
  is 
  a 
  continuous 
  amelioration 
  of 
  the 
  method 
  

   of 
  selecting. 
  It 
  is 
  manifest 
  that 
  the 
  progres- 
  

   sion 
  of 
  the 
  race 
  is 
  in 
  the 
  main 
  due 
  to 
  great 
  tech- 
  

   nical 
  improvements, 
  and 
  not 
  solely 
  to 
  the 
  repe- 
  

   tition 
  of 
  the 
  selection. 
  

  

  Similar 
  facts 
  may 
  be 
  seen 
  on 
  all 
  the 
  great 
  

   lines 
  of 
  industrial 
  selection. 
  An 
  increasing 
  ap- 
  

  

  