﻿254 
  ANNUAL 
  EEPOKT 
  SMITHSONIAN 
  INSTITUTION, 
  19 
  29 
  

  

  which 
  the 
  man 
  in 
  the 
  street, 
  borrowing 
  from 
  the 
  use 
  of 
  the 
  word 
  

   in 
  the 
  moral 
  sphere, 
  attaches 
  to 
  it 
  when 
  it 
  is 
  appHed 
  in 
  the 
  domain 
  

   of 
  material 
  things. 
  As 
  a 
  matter 
  of 
  fact, 
  the 
  "impurities" 
  present 
  

   in 
  natural 
  products 
  often 
  enhance 
  their 
  value 
  judged 
  from 
  human 
  

   standpoints. 
  Thus, 
  from 
  a 
  purely 
  chemical 
  point 
  of 
  view, 
  the 
  trace 
  

   of 
  cholesterol 
  in 
  cod-liver 
  oil 
  is 
  an 
  impurity, 
  the 
  trace 
  of 
  ergosterol 
  

   an 
  impurity 
  in 
  the 
  cholesterol, 
  and 
  the 
  trace 
  of 
  vitamin 
  D 
  an 
  impurity 
  

   in 
  the 
  ergosterol. 
  It 
  is 
  just 
  this 
  last 
  impurity, 
  however, 
  which 
  makes 
  

   cod-liver 
  oil 
  so 
  valuable 
  a 
  preventive 
  of 
  rickets. 
  

  

  I 
  take 
  another 
  illustration 
  more 
  cognate 
  to 
  the 
  subject 
  of 
  synthetic 
  

   perfumes. 
  The 
  natural 
  perfume 
  material 
  of 
  jasmine 
  has 
  been 
  

   pretty 
  completely 
  analyzed. 
  It 
  consists 
  mainly 
  of 
  benzyl 
  acetate, 
  

   a 
  substance 
  easily 
  synthesized 
  from 
  toluene. 
  Now, 
  benzyl 
  acetate 
  

   has 
  a 
  pleasant 
  odor, 
  reminding 
  one 
  very 
  strongly 
  of 
  that 
  of 
  jasmine 
  

   flowers; 
  but 
  it 
  is 
  certainly 
  very 
  inferior 
  to 
  this. 
  The 
  natural 
  jasmine 
  

   odor 
  owes 
  its 
  perfection 
  to 
  the 
  presence 
  of 
  other 
  odorous 
  bodies 
  in 
  

   association 
  with 
  the 
  benzyl 
  acetate, 
  of 
  which 
  the 
  most 
  important 
  

   are 
  benzyl 
  alcohol, 
  linalol, 
  linalyl 
  acetate, 
  methyl 
  anthranilate, 
  indole, 
  

   and 
  a 
  ketonic 
  body 
  called 
  "jasmone." 
  

  

  In 
  the 
  cases 
  of 
  many 
  pleasantly 
  odorous 
  plants, 
  the 
  main 
  constit- 
  

   uent 
  of 
  the 
  natural 
  otto 
  is 
  known, 
  as 
  well 
  as 
  the 
  chemical 
  composition 
  

   of 
  the 
  main 
  "impurities," 
  or, 
  if 
  the 
  word 
  seems 
  a 
  misnomer, 
  let 
  us 
  

   say 
  "subsidiary 
  substances." 
  Nowadays, 
  it 
  is 
  usually 
  a 
  short 
  step 
  

   from 
  the 
  discovery 
  of 
  the 
  chemical 
  composition 
  of 
  a 
  substance 
  to 
  

   its 
  synthetic 
  production, 
  and, 
  in 
  many 
  cases, 
  these 
  substances 
  have 
  

   been 
  synthetically 
  prepared. 
  One 
  can 
  say, 
  practically 
  as 
  a 
  general 
  

   rule, 
  that 
  the 
  odor 
  of 
  the 
  main 
  substance 
  gives 
  a 
  crude 
  representation 
  

   of 
  the 
  natural 
  perfume 
  of 
  a 
  flower. 
  This 
  odor 
  is 
  much 
  improved 
  by 
  

   the 
  addition 
  of 
  suitable 
  proportions 
  of 
  the 
  subsidiary 
  substances. 
  

   It 
  still, 
  however, 
  almost 
  invariably 
  falls 
  short 
  of 
  perfection; 
  the 
  

   reason 
  being 
  that 
  there 
  are 
  further 
  "impurities" 
  present 
  in 
  most 
  

   minute 
  traces 
  in 
  the 
  natural 
  otto, 
  which 
  chemical 
  analysis 
  hsis 
  failed 
  

   to 
  identify, 
  but 
  whose 
  odors 
  play 
  their 
  part 
  in 
  producing 
  the 
  frigrance 
  

   of 
  the 
  flower. 
  '\ 
  

  

  Two 
  important 
  points 
  emerge; 
  first, 
  the 
  fact 
  that 
  extraordinarily 
  

   small 
  amounts 
  of 
  certain 
  substances 
  are 
  capable 
  of 
  excitibg 
  the 
  

   sense 
  of 
  smell, 
  and 
  may 
  by 
  their 
  presence 
  or 
  otherwise 
  modfy 
  the 
  

   odor 
  of 
  a 
  perfume; 
  and, 
  secondly, 
  the 
  fact 
  that 
  substances 
  whose 
  

   odors 
  are 
  unpleasant 
  in 
  a 
  pure 
  state 
  may 
  develop 
  a 
  pleasant 
  fragrance 
  

   in 
  a 
  state 
  of 
  extreme 
  dilution 
  and 
  play 
  an 
  essential 
  part 
  in 
  imploving, 
  

   from 
  an 
  esthetic 
  point 
  of 
  view, 
  the 
  fragrance 
  of 
  a 
  perfume. 
  Indole, 
  

   present 
  in 
  the 
  natural 
  otto 
  of 
  the 
  jasmine, 
  is 
  a 
  case 
  in 
  point. 
  Skatole, 
  

   whose 
  odor 
  is 
  one 
  of 
  the 
  most 
  unpleasant 
  conceivable, 
  affot'ds 
  an 
  

   even 
  more 
  strildng 
  instance, 
  since, 
  used 
  in 
  tiny 
  traces, 
  this 
  substance 
  

   is 
  distinctly 
  valuable 
  in 
  compounding 
  certain 
  perfumes. 
  

  

  