RESEARCHES  ON  BUCKWHEAT. 
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generally,  a  wholesome  and  sufficiently  reparatory  nourishment ; 
there  exists  between  the  two  principal  kinds  of  buck-wheat  flour 
which  are  found  in  commerce,  a  difference  of  richness  in  nitro- 
genous principles,  which  may  be  estimated  as  averaging  45  per 
cent. 
The  coarsest  and  least  white  of  the  two  is  the  richest  in  nitro- 
genous principles,  phosphates  and  fatty  matters  ;  this  is  conse- 
quently the  most  nutritious,  and  it  is  thus  easy  to  see  that  it 
may  form  the  sole  food  of  the  rural  population  in  some  countries. 
The  preparations  known  as  buck- wheat  cakes,  form  a  food  which 
is  comparable  to  the  ordinary  bread  of  Paris,  as  regards  the  pro- 
portion of  phosphates  and  nitrogenous  principles  which  it  con- 
tains, and  which  is  superior  to  it  with  regard  to  the  fatty  matters. 
The  general  yield  of  these  preparations,  when  properly  cooked, 
is  about  three  times  the  weight  of  the  flour  used ;  they  contain, 
therefore,  from  40  to  41  per  cent,  of  water  :  this  yield  appears 
to  be  nearly  independent  of  the  mode  of  preparation,  provided 
the  cakes  are  properly  cooked.  There  may  be,  between  the 
various  products  of  the  grinding  of  one  batch  of  buck- wheat,  with 
respect  to  their  richness  in  nitrogen,  phosphates  and  fatty 
matters,  such  differences,  that  one  contains  nearly  seven  times 
as  much  nitrogen,  twenty-five  times  as  much  phosphates,  and  a 
hundred  and  fifteen  times  as  much  patty  matters,  as  another; 
the  coarsest  flour  may  contain  twice  as  much  nitrogen,  four 
times  and  a  half  as  much  phosphate,  and  two  and  a  half  times 
as  much  fatty  matters,  as  an  equal  weight  of  the  buck-wheat 
which  furnished  it ;  the  bran  which  proceeds  from  the  ordinary 
grinding  of  buck- wheat  is  richer  in  nitrogen  phosphates  and  fatty 
matters  than  the  whole  grain  from  which  it  proceeds,  and  it  would 
be  possible  by  a  perfect  method  of  bolting  in  separate  a  fari- 
naceous product,  which  would  be  much  richer  to  nitrogen,  in 
phosphate,  and  especially  in  fatty  matters  than  ordinary  flour. 
As  has  been  observed  with  ordinary  wheat,  the  finest  and  most 
nourishing  buck-wheat  is  not  that  which  contains  the  largest  pro- 
portions of  the  principles,  to  which  the  most  importance  has  been 
attached  for  alimentation.  The  differences  of  composition  ob- 
served between  the  various  products  obtained  in  grinding  buck- 
wheat are  much  more  distinct  than  the  analogous  differences 
