﻿SOLAR 
  ENERGY 
  — 
  SPOEHR. 
  183 
  

  

  It 
  seems 
  highly 
  questionable 
  whether 
  the 
  use 
  of 
  the 
  products 
  of 
  

   photosynthesis 
  offers 
  a 
  rational 
  solution 
  to 
  the 
  problem 
  of 
  industrial 
  

   energy. 
  It 
  must 
  be 
  borne 
  in 
  mind 
  that 
  the 
  products 
  of 
  photosyn- 
  

   thesis 
  are 
  essential 
  to 
  human 
  life 
  as 
  the 
  fundamental 
  source 
  of 
  food. 
  

   The 
  trend 
  of 
  modern 
  investigation 
  of 
  the 
  chemical, 
  as 
  well 
  as 
  the 
  

   economic 
  phases 
  of 
  the 
  food 
  problem, 
  strongly 
  supports 
  the 
  dictum 
  

   that 
  agriculture 
  will 
  always 
  be 
  the 
  basis 
  of 
  food 
  production 
  and 
  that 
  

   this 
  can 
  not 
  be 
  supplanted 
  by 
  any 
  artificial 
  method. 
  The 
  materials 
  

   which 
  are 
  elaborated 
  by 
  plants 
  are 
  directly 
  essential 
  to 
  the 
  well-being 
  

   of 
  man. 
  Furthermore, 
  any 
  serious 
  disturbance 
  in 
  the 
  way 
  of 
  divert- 
  

   ing 
  agricultural 
  products 
  from 
  their 
  use 
  as 
  food 
  to 
  industrial 
  ends 
  

   would 
  undoubtedly 
  be 
  fraught 
  with 
  profound 
  economic 
  disturbances. 
  

  

  CELLULOSE 
  AS 
  SOURCE 
  OF 
  FUEL. 
  

  

  There 
  is 
  one 
  other 
  plant 
  product 
  about 
  which 
  there 
  has 
  been 
  much 
  

   speculation 
  regarding 
  the 
  possibilities 
  as 
  a 
  source 
  of 
  liquid 
  fuel; 
  that 
  

   is 
  cellulose. 
  There 
  are 
  so 
  many 
  factors 
  which 
  enter 
  into 
  a 
  rational 
  

   consideration 
  of 
  the 
  possibilities 
  of 
  producing 
  alcohol 
  from 
  cellulose 
  

   that 
  no 
  adequate 
  analysis 
  of 
  the 
  problem 
  has 
  as 
  yet 
  been 
  attained. 
  

   These 
  factors 
  embody 
  the 
  biological 
  aspects, 
  the 
  chemical 
  methods, 
  

   and 
  the 
  economic 
  possibilities. 
  It 
  can 
  not 
  be 
  claimed 
  that 
  any 
  one 
  

   of 
  the 
  many 
  compilations 
  and 
  discourses 
  offered 
  since 
  the 
  great 
  

   interest 
  in 
  this 
  subject 
  has 
  arisen 
  treat 
  adequately 
  the 
  complexities 
  of 
  

   the 
  problem. 
  Briefly, 
  the 
  points 
  that 
  demand 
  consideration 
  are 
  the 
  

   availability 
  of 
  cellulose 
  material 
  in 
  sufficient 
  quantity 
  and 
  the 
  con- 
  

   tinuous 
  supply 
  thereof, 
  an 
  exact 
  and 
  broad 
  knowledge 
  relative 
  to 
  the 
  

   chemical 
  processes 
  of 
  converting 
  cellulose 
  to 
  alcohol, 
  and 
  the 
  cost 
  of 
  

   raw 
  material, 
  manufacture, 
  and 
  transportation, 
  as 
  well 
  as 
  the 
  com- 
  

   plexities 
  of 
  labor 
  and 
  influence 
  on 
  other 
  industries. 
  In 
  different 
  

   sections 
  of 
  the 
  country 
  where 
  different 
  kinds 
  of 
  wood 
  come 
  into 
  con- 
  

   sideration 
  there 
  are 
  problems 
  peculiar 
  to 
  each 
  locality. 
  

  

  Much 
  of 
  the 
  speculation 
  as 
  to 
  the 
  use 
  of 
  cellulose 
  for 
  conversion 
  

   into 
  alcohol 
  is 
  based 
  upon 
  the 
  utilization 
  of 
  waste 
  material 
  in 
  the 
  

   forests 
  and 
  at 
  the 
  mills. 
  Of 
  the 
  26,000,000,000 
  cubic 
  feet 
  of 
  wood 
  

   cut 
  annually, 
  the 
  major 
  portion 
  represents 
  accumulated 
  virgin 
  tim- 
  

   ber, 
  so 
  that 
  this 
  source 
  can 
  not 
  be 
  considered 
  as 
  a 
  permanent 
  one. 
  To 
  

   what 
  extent 
  and 
  how 
  soon 
  the 
  depletion 
  of 
  virgin 
  forests 
  will 
  be 
  met 
  

   by 
  intensive 
  forestry 
  is 
  a 
  practical 
  question 
  that 
  seems 
  difficult 
  to 
  

   answer. 
  

  

  These 
  considerations 
  also 
  obtain 
  for 
  the 
  frequently 
  repeated 
  state- 
  

   ments 
  of 
  the 
  use 
  of 
  humid 
  tropical 
  regions 
  for 
  growing 
  material 
  

   from 
  which 
  alcohol 
  could 
  be 
  manufactured. 
  It 
  must 
  be 
  borne 
  in 
  

   mind 
  that 
  for 
  any 
  such 
  undertaking 
  reliance 
  could 
  not 
  be 
  placed 
  

   upon 
  extant 
  material, 
  recourse 
  would 
  have 
  to 
  be 
  taken 
  to 
  very 
  ex- 
  

  

  