560 
ANALYSIS  OF  BEEF  MARROW. 
1806,  ii.)  and  treats  chiefly  of  its  general  properties;  Jahn 
(Chem.  Tab.  1814)  merely  gives  a  short  note,  that  it  Was 
apparently  composed  of  two  fats, — one  of  which  was  liquid,  and 
could  be  separated  from  the  solid  by  filtration.  According  to 
Berzelius,  ox  marrow  fuses  at  45°  C,  is  saponifiable  by  alkalies, 
slightly  soluble  in  boiling  alcohol,  separating  on  cooliflg  as  a 
white  flocculent  powder,  and,  with  difficulty,  soluble  in  ether ;  he 
likewise  subjected  it  to  dry  distillation,  and  to  the  action  of 
sulphuric  and  nitric  acids. 
Dr.  Eylerts  prepared  the  pure  fat  from  the  marrow,  which 
was  of  a  yellowish  white  color,  inodorous,  of  a  mild  taste, 
and,  after  four  months,  showed  no  disposition  to  rancidity. 
It  was  drawn  into  a  capillary  tube,  having  some  air  between 
the  several  drops,  and  fused  then  at  45-°5  C.  (J13-°9  F.),  and 
congealed  at  35°  C.  (95QF.)  It  is  soluble  at  12°  C.  in  42  p. 
ether  of  -730  sp,  gr.  in  2420  p.  alcohol  of  90  per  ct.?  and  in 
40  p.  oil  of  turpentine.  Boiling  ether  and  oil  of  turpentine 
dissolve  nearly  their  own  weight,  boiling  alcohol  l-150th. 
In  order  to  determine  the  fatty  acids,  the  marrow  fat  was 
saponified  with  potassa  and  the  soap  decomposed  with  diluted 
sulphuric  acid.  The  mother  liquor  contained  no  volatile  acid ; 
but  yielded,  by  evaporation  and  treating  with  alcohol,  almost 
4  per  ct.  of  syrupy  sweet  glycerine. 
The  fatty  acids  were  fused  with  water  and  combined  with 
potassa ;  the  soap  was  decomposed  by  chloride  of  sodium,  and 
the  amount  of  magnesia  determined  necessary  for  the  complete 
precipitation.  One  hundred  and  twenty  grs.  of  soda  soap 
yielded  234  grs.  (?)  of  magnesia  soap,  which  contained  5-85  grs. 
of  magnesia. 
Six  oz.  of  the  soap  was  now  dissolved  in  60  oz.  of  86  per  ct. 
alcohol  and  precipitated  with  one-fourth  the  requisite  quantity 
of  acetate  of  magnesia  dissolved  in  alcohol ;  this  fractional 
precipitation  was  repeated  twice  after  the  separation  of  the 
precipitate. 
Each  of  the  precipitates  was  fused  with  dilute  hydrochloric 
acid  until  all  the  magnesia  had  been  removed ;  the  fat  was  freed 
from  the  acid,  and  dissolved  in  hot  alcohol,  from  which  a  portion 
separated,  after  cooling,  in  loose  crystalline  laminae.  This 
crystalline  precipitate  was  repeatedly  treated  with  hot  alcohol 
