$8 
VARIETIES. 
well  with,  about  6  cwt.  of  boiling  water ;  8  cwt.  of  milk  of  lime,  about  the 
consistense  of  cream,  are  then  added.  When  the  flour  and  lime  are  well 
mixed  together,  10  cwt  of  fresh  rosin  oil  are  added,  and  the  whole  well 
stirred  until  the  mass  becomes  thoroughly  mixed,  and  of  a  thick  consist- 
ence. 
No.  3.— A  fluid  lubricating  compound,  to  be  used  as  a  substitute  for  oil, 
may  be  made  by  mixing  together  3  cwt,  of  liquid  linseed  or  diluted  rice 
pulp,  1  cwt.  of  linseed  oil,  1  cwt.  of  rape  oil,  and  14  lbs.  of  soda  solution. 
The  liquid  linseed  is  prepared  by  boiling  1  cwt.  of  linseed  with  q.  s.  of  water 
to  yield  a  product  weighing  about  12  cwt.  of  a  thickish  consistence.  The 
soda  solutionis  prepared  by  dissolving  28  lbs.  of  soda  in  2  cwt.  of  water. — ■ 
Annals  of  Pharmacy. 
Preparation  of  Uric  Acid  from  the  Excrements  of  Pigeons.  By  A.  E. 
Arppe. — In  a  capacious  copper  boiler,  10  ounces  of  borax  were  dissolved 
in  70  pounds  of  water.  Into  this  solution  two  linen  bags,  each  containing 
3|  pounds  of  the  dried  excrements  of  pigeons,  were  introduced,  and  boiled 
one  hour,  and  stirred  ;  after  which,  the  bags  were  removed  and  allowed  to 
drain.  In  the  boiling  borax  solution  §  pound  of  sal-ammoniac  was  dis- 
solved, the  vessel  then  removed  from  the  fire,  and  allowed  to  cool.  After 
12  hours,  a  considerable  greyish  white  precipitate  of  urate  of  ammonia 
was  deposited  at  the  bottom  of  the  vessel.  The  above  clear,  strongly 
brown  colored  fluid  was  removed  with  a  syphon,  fresh  water  poured  tm, 
and  this  operation  repeated  until  the  liquid  had  become  quite  colorless^ 
The  precipitate  was  then  again  boiled  with  a  week  solution  of  borax,  by 
which  a  large  quantity  of  a  slimy  mass  remained  undissolved.  The  solu- 
tion, which  can  now  be  filtered  through  paper,  and  is  colored  slightly 
brown,  is  warmed  and  poured  into.a  warm  mixture,  consisting  of  §  ounce 
of  sulphuric  acid,  with  1  ounce  of  water.  After  cooling,  the  uric  acid 
separates  in  the  crystalline  form.  It  is  colored  light  brown,  and  is  puri- 
fied by  solution  in  potash,  evaporation  of  the  liquid,  and  a  repetition  of  this 
operation,  and,  lastly,  by  decomposition  with  sulphuric  acid.  I  have  in 
this  way  obtained  A  per  cent,  of  quite  snow  white  uric  acid  from  the  ex- 
crements of  pigeons,  and  believe  the  modifications  here  described  in  the 
mode  of  the  preparation  of  this  important  acid  to  be  practically  valuable, 
as  opportunity  is  very  seldom  afforded  to  procure  it  from  the  more  abun- 
dant excrements  of  serpents. — Ibid,  from  Liebig's  Annalen. 
New  Gutta  Percha  Cements. — For  uniting  sheet  gutta  percha  to  silk  or 
other  fabrics  :  Gutta  percha,  40  lbs. ;  caoutchouc,  3  lbs. ;  shellac,  3  lbs. ;  Ca- 
nada balsam,  or  Venice  turpentine,  14  lbs. ;  liquid  styrax,  35  lbs. ;  gum 
mastic,  4  lbs. ;  oxide  of  lead,  1  lb. 
For  uniting  sheet  gutta  percha  to  leatlier,  as  soles  of  shoes,  &c. :  Gutta 
percha  50  lbs. ;  Venice  turpentine,  40  lbs. :  shellac,  41bs. ;  caoutchouc,  1  lb.; 
liquid  styrax  5  lbs. — Annals  of  Pharmacy,  Dec.  1853. 
