ALUM  IN  CHINA. 
71 
were  adjacent  to  the  quarries  from  which  the  alum-stone  seemed 
to  crop  out  of  decomposed  rock  of  the  same  lithological  charac- 
ter. The  stones  were  thrown  into  a  fire  of  brushwood,  where 
they  were  burnt  with  a  slight  lambent  flame,  and  as  they  cracked, 
the  fragments  were  raked  out,  broken  into  small  pieces,  and 
macerated  in  vats.  Subsequently  the  disintegrated  mineral  was 
thrown  with  water  into  a  vessel  having  an  iron  bottom  and  sides 
of  wood,  and  boiled  for  a  short  time.  The  lixivium  was  then 
poured  into  large  reservoirs,  where  it  crystallized  into  a  solid 
mass.  Blocks  of  alum,  weighing  about  fifty  catties  each,  were 
hewn  out  of  the  reservoir  and  carried  in  this  state  in  bamboo 
frames,  one  on  each  end  of  a  porter's  pole  to  the  place  of  ship- 
ment, where  it  is  broken  into  fragments.  When  not  designed 
for  immediate  exportation  the  blocks  are  stored  away  for  dry- 
ing. On  reaching  the  depot  the  alum  is  found  charged  with  a 
double  quantity  of  moisture  ;  the  porters  being  obliged  to  deliver 
a  certain  weight,  they  slip  their  burdens  in  the  mountain  streams 
which  they  pass  in  the  journey. 
Judging  from  the  number  of  laborers  engaged  in  transporting 
the  mineral  on  the  day  of  our  informant's  visit,  the  quantity 
brought  from  the  works  could  not  be  less  than  eighteen  tons. 
This  was  represented  as  less  than  an  average  day's  work,  as 
labor  was  in  such  demand  just  then  for  agricultural  purposes, 
that  double  pay  was  given  ; — and  aged  men,  and  women,  with 
boys  and  girls  were  pressed  into  the  service.  Assuming  that 
day's  product  as  a  basis  for  calculation,  and  making  an  allow- 
ance for  rainy  days,  we  may  safely  estimate  the  annual  supply 
as  between  five  and  six  thousand  tons.  The  quantity  consumed 
by  the  dyers  of  Ningpo  prefecture  alone,  being  nearly  twenty- 
two  tons  per  annum  is  corroborative  of  this  estimate.  The 
supply  is  literally  inexhaustible.  Five  dollars  and  a  quarter  a 
ton  at  the  landing  would  afford  the  manufacturer  a  fair  profit. 
It  often  fetches  much  more,  as  there  has  been  an  increasing  de- 
mand for  the  article,  owing  to  the  greater  facilities  afforded  for 
exportation  from  Ningpo  in  foreign  vessels. — American  Journal 
of  Science  and  Arts,  November,  1858. 
