4 
ON  THE  GUM-KESIN  OF  THE  BALSAM  OF  PERU  TREE.  143 
ing  free  sulphur  imbedded  in  gypsum  were  imported  from  the 
Island  of  Milo,  in  the  Archipelago.  From  the  small  quantity  of 
sulphur  contained  in  it  (19  up  to  21  per  cent.)  there  wall  great 
difficulty  found  in  burning  it,  except  the  large  masses.  Subjoined 
is  an  analysis  of  one  parcel  of  it : — Sulphur,  24  00 ;  gypsum, 
62-20;  sand,  &c,  6-00;  water,  7-00.  Still  more  recently,  Pro- 
fessor Anstead  has  discovered  a  deposit  of  free  sulphur  in  Corfu, 
of  which  he  has  been  kind  enough  to  forward  a  sample,  but  we 
believe  it  has  not  been  used  in  commerce.  When  sulphuric  acid 
is  wanted  quite  free  from  arsenic,  Sicilian  sulphur  must  be  used. 
So  largely  has  pyrites  displaced  sulphur  in  the  production  of  sul- 
phuric acid,  that  in  1862  only  2030  tons  of  sulphur  were  con- 
sumed, against  72,800  tons  of  pyrites;  and,  reckoning  the  above 
quantity  of  sulphur  as  equivalent  to  4500  tons,  it  appears  that 
77,300  tons  of  pyrites  are  annually  used  for  the  manufacture  of 
sulphuric  acid,  along  with  2500  tons  of  nitrate  of  soda.  Assum- 
ing a  produce  of  120  per  cent,  on  the  pyrites,  this  is  equal  to  a 
production  of  92,760  tons  of  sulphuric  acid,  calculated  as  concen- 
trated. This  quantity  of  sulphuric  acid  is  nearly  all  consumed 
where  it  is  made,  for  the  manufacture  of  other  chemicals,  such  as 
soda  and  manures,  the  quantity  sold  being  64-40  tons  ;  but  thia 
might  be  more  correctly  described  as  consumed  in  other  works, 
for  the  quantity  sent  to  a  distance  is  very  small.  Four-fifths  of 
the  sulphuric  acid  is  used  for  the  decomposition  of  common  salt 
—Chem.  News,  Sept.  12,  1863. 
NOTE  ON  THE  GUM-RESIN  OF  THE  BALSAM  OF  PERU  TREE, 
By  Dr.  Attfield. 
The  naturally-exuded  resin  of  the  Myroxylon  Pereirce,  as  fur- 
nished to  me  by  Mr.  Hanbury,  consists  of 
In  100  parts 
Resin  77*4 
Gum  17-1 
Woody  fibre  1-5 
Water  and  a  small  quantity  of  volatile  oil,  about  4-0 
The  resin  is  an  acid,  its  alcoholic  solution  feebly  reddening  lit- 
mus-paper, and  is  uncrystallizable.    The  gum  is  similar  to  that 
of  gum  arabic.    The  volatile  oil  is  limpid,  colorless  and  fragrant. 
