102 
ANALYSIS  OF  A  CONCRETION. 
superstitious,  they  are  called  witch-balls ;  but  their  origin  is  suffi- 
ciently obvious  to  the  intelligent  observer. 
The  concretion  in  question,  after  being  dried  at  a  temperature  of 
about  70°  for  several  weeks,  weighed  but  209  grs.  It  had  no 
taste  nor  smell,  except  a  very  faint  cow-house  odor;  and  apparent- 
ly consisted  altogether  of  hairs,  loosely  felted  together. 
On  subjecting  it  to  the  action  of  water  at  the  temperature  of  40° 
only,  I  obtained  a  brown  liquid,  which  was  neutral  to  test  papers, 
and  produced  no  precipitate  by  boiling.  Acids  caused  a  precipitate 
which  was  immediately  dissolved  by  the  excess  of  the  reagent. 
The  brown  liquid  acidulated  by  exceedingly  dilute  HC1  yielded  a 
white  precipitate  to  Cfy  +  2K. 
These,  and  other  reactions  indicated  the  existence  of  C  as  tin* 
The  residue  of  the  concretion  was  treated  with  a  fresh  supply  of 
water  at  135°  for  one  or  two  hours.  The  filtrate  was  much  paler 
than  that  of  the  first  maceration ;  and  yielded  the  same  results,  but 
in  a  less  degree. 
The  washed  residue  presented  to  the  eye  a  mass  of  yellowish  brown 
hairs,  and  of  light  brown,  irregular  formed  concretions  of  various 
sizes.  The  hairs  were  carefully  removed,  and  a  portion  of  the 
residue  rubbed  between  the  fingers  imparted  an  unctuous  or  soap- 
stone  feeling.  A  small  quantity  stirred  in  alcohol,  readily  separat- 
ed ;  and  when  placed  under  the  microscope,  appeared  to  be  wholly 
epithelial  scales  ;  they  burnt  like  horn,  and  evolved  a  similar  odor. 
Treating  the  epithelium  with  alcohol  (.810)  and  evaporating 
the  filtrate,  which  was  of  a  rich  golden  yellow,  I  obtained  a  watery 
looking  fluid;  and  separated  from  it  an  orange  red  mushy  matter. 
The  limpid  fluid  promptly  reddened  litmus,  and  evaporated  at  less 
than  50°  so  rapidly  as  to  appear  to  effervesce.  An  ethereal  filtrate 
furnished  a  corresponding  result.  The  scantiness  of  my  material 
allowed  me  no  opportunity  to  examine  it  further,  except  that  it  left 
no  grease  spot  upon  paper.   I  set  it  down  as  Butyric  Acid. 
The  orange  red  portion  heated  beyond  212°,  gives  out  a  strong 
cow-house  odor  ;  and  evaporates  with  a  smoky  vapor,  leaving  a 
slight  residue.  It  has  no  acid  reaction,  leaves  a  greasy  stain  when 
warmed  on  paper,  and  is  not  saponifiable  in  a  solution  of  potash, 
at  boiling  heat.  From  the  alcoholic  solution,  bichloride  of  mer- 
cury and  diacetate  of  lead  precipitate  beautiful  white  crystalline 
