Am.  Jour.  Pharm.l 
November,  1900.  / 
Technical  Chemistry. 
545 
casting  machine  of  Uehling  for  handling  the  metal,  and  the  various 
methods  for  carrying  charges  to  the  furnace  top,  with  automatic 
dumping  and  distributing  devices.  These  latter  have  removed  the 
necessity  for  charging  men  or  any  laborers  continuously  at  the 
charging  level,  where  the  work  is  exhausting  and  dangerous.  By 
the  use  of  a  double  bell  they  effect  a  thorough  mixture  of  the 
charge  and  prevent  the  loss  of  furnace  gases. 
The  successful  conversion  of  blast  furnace  slag  into  a  fair  quality 
of  hydraulic  cement  at  a  number  of  furnaces  is  a  long  step  toward 
the  economical  solution  of  the  troublesome  problem  of  the  disposal 
of  this  vast  by-product.  It  has  been  found  that  certain  grades  of 
basic  slag  in  which  the  proportion  of  magnesia  and  sulphur  is  not 
too  high,  by  simply  being  granulated  with  water  as  they  flow  from 
the  furnace,  ground  extremely  fine  and  intimately  mixed  with  the 
proper  proportion  of  lime,  are  converted  into  a  hydraulic  cement 
which  forms  a  cheap  and,  under  certain  conditions,  an  excellent 
substitute  for  Portland  cement,  and  for  which  a  permanent  demand 
has  been  created. 
In  the  production  of  steel  the  gap  between  the  cost  ot  producing 
Bessemer  and  open-hearth  metal  has  been  further  lessened,  mainly 
by  the  general  introduction  of  basic  open-hearth  furnaces  of  greatly 
increased  capacity  and  of  labor-saving  devices  in  charging  metal 
and  fluxes.  Most  important  of  these  latter  is  the  charging  machine 
of  Wellman.  In  this  connection,  too,  the  large  introduction  of  the 
Wellman  tilting  open-hearth  furnace  during  1899  is  worthy  of  men- 
tion, and  a  probable  further  economy  of  operation  will  be  secured 
by  their  use.  Several  large  plants  using  these  tilting  furnaces  have 
been  installed  during  the  past  year,  and,  while  they  have  been  used 
in  a  number  of  places  heretofore,  the  record  of  their  efficiency  has 
not  as  yet  been  made  public  and  is  awaited  with  great  interest. 
While  their  cost  of  construction  is  about  25  per  cent,  more  than 
that  of  the  older  stationary  type,  the  complete  removal  of  all  metal 
and  slag  from  the  furnace  hearth  at  each  operation,  with  the  result- 
ing saving  of  metal,  the  saving  of  the  time  necessary  for  tapping, 
the  small  amount  of  repair  necessary  to  the  bed  after  the  removal 
of  each  charge,  and  the  facility  with  which  this  can  be  accomplished 
are  factors  which  will  probably  cause  this  to  become  the  standard 
type  of  steel  furnace  of  this  decade. 
In  Bessemer  practice  the  most  noticeable  improvement  is  the 
