Am.  Jour.  Pharra. 
Feb.,  1886. 
Whiting  and  Its  Manufacture. 
77 
Sangre  de  drago.  Besides  the  •  commercial  dragon's  blood,  this 
name  is  applied  in  Mexico  to  the  resins  of  several  plants,  chiefly  to 
that  of  Pterocarpus  Draco  Lin.  (Leguininosse)  and  of  Croton  sangui- 
fluum,  Kunih  (Euphorbiacese),  the  latter  known  as  "  Ezquahuitl"  or 
"  Arbol  de  sangre."  The  jnice  and  the  branches  of  these  plants  are 
astringent. 
ON  WHITING  AND  ITS  MANUFACTURE. 
By  Joseph  W.  England,  Ph.  G. 
(Read  at  the  Pharmaceutical  Meeting,  January  19th.) 
Among  the  varied  industries  whose  products  have  found  general 
employment  and  received  numerous  applications  in  the  arts  and  scien- 
ces, the  preparation  of  purified  chalk  may  properly  claim  our  attention, 
and  a  few  remarks  incidental  to  its  commercial  history  and  preparation 
for  market,  may  be  of  interest. 
Amongst  its  many  applications  we  quote :  For  medicinal  purposes 
in  the  form  of  the  so-called  "Creta  Praeparata"  we  find  it  internally 
employed  for  its  well-known  antacid  and  astringent  qualities,  or  exter- 
nally for  the  healing  of  burns,  ulcers,  intertrigo  and  other  cuticular 
affections ;  and  then,  chemically,  for  the  preparation  of  various  lime- 
salts.  Moulders  use  its  finest  grades,  in  connection  with  plastic  clay 
and  glue,  in  the  mouldings  upon  picture  frames,  preparatory  to  gild- 
ing ;  while  in  oil-cloth  manufacture,  it  serves  as  a  basis  in  the  applica- 
tion of  other  materials.  Mixed  with  a  variety  of  colors,  it  forms  the 
water-color  pigments,  and  is  also  utilized  in  the  sizing  of  wall  papers. 
When  strongly  heated  it  may  readily  be  converted  into  lime  and  used 
either  as  a  cement  in  connection  with  other  materials  or  for  fertilizing 
land ;  the  immediate  effect  being  to  render  the  soil  more  able  to  retain 
moisture  and  to  improve  its  texture.  It  is  very  largely  used  as  a 
basis  for  some  cheap  colored  paints,  but  its  great  lack  of  the  body  that 
characterizes  the  lead  product,  prevents  its  more  general  adoption,  ex- 
cept as  an  adulterant.  Latterly,  it  has  been  applied  in  the  preparation 
of  carbonated  waters  by  mineral  water  manufacturers,  some  of  whom 
state  that  the  relative  proportion  of  marble  dust  used  to  whiting  is  as 
1:3  or  4.  Its  well-known  cleaning  properties  upon  glass,  or  metallic 
surfaces,  when  freed  from  hard,  crystalline  siliceous  particles,  to  pre- 
vent scratching,  and  its  use  in  making  putty  with  linseed  oil,  are  too 
well-known  to  require  more  than  mere  passing  comment. 
