ITO       A  NEWLY-DISCOVERED  PROPERTY  OP  GUN-COTTON. 
lieved,  that  unconfined  gun-cotton  was  scarcely  to  be  considered 
as  explosive  at  all,  that  it  puflfed  harmlessly  away  into  the  air, 
not  exerting  sufficient  force  upon  the  body  on  which  it  might 
be  resting  to  depress  a  nicely  balanced  pair  of  scales,  suppos- 
ing the  charge  to  be  fired  upon  one  plate  of  the  scale.  Further, 
long  charges  or  trains  of  gun-cotton,  simply  placed  upon  the 
ground  against  stockades  of  great  strength,  and  wholly  uncon- 
fined, have  been  exploded  by  means  of  detonating  fuzes  placed 
in  the  centre  or  at  one  end  of  the  train,  and  produced  uni- 
formly destructive  efi*ects  throughout  their  entire  length,  the 
results  corresponding  to  those  produce  by  eight  or  ten  times  the 
amount  of  gunpowder  when  applied  under  the  most  favorable 
conditions.  Mining  and  quarrying  operations  with  gun-cotton 
applied  in  the  new  manner  have  furnished  results  quite  equal  to 
those  obtained  with  nitro-glycerin,  and  have  proved  conclusive- 
ly that  if  gun-cotton  is  exploded  by  detonation  it  is  unnecessary 
to  confine  the  charge  in  the  blast-hole  by  the  process  of  hard- 
tamping,  as  the  explosion  of  the  entire  charge  takes  place  too 
suddenly  for  its  effects  to  be  appreciably  diminished  by  the  line 
of  escape  presented  by  the  blast-hole.  Thus  the  most  danger- 
ous of  all  operations  connected  with  mining  may  be  dispensed 
with  when  gun-cotton*fired  by  the  new  system  is  employed.  It 
will  readily  be  observed  that  this  discovery,  which  we  believe  is 
due  to  Mr.  Brown,  of  the  War  Office  Chemical  Establishment, 
is  likely  to  be  attended  with  the  most  important  results.  Not 
merely  is  the  strength  of,  gun-cotton  exploded  in  this  way  much 
greater  than  that  of  the  same  substance  fired  by  simple  ignition, 
but  it  now  operates  under  conditions  which  were  sufficient  under 
the  old  system  practically  to  deprive  gun-cotton  of  its  power. 
It  has  been  said,  and  said  justly,  that  if  you  want  gun-cotton  to 
exert  itself  you  must  coax  it  into  the  belief  that  it  has  a  great 
deal  to  do.  You  must  give  it  bonds  to  break  and  physical 
obstacles  to  overcome,  with  no  outlet  or  possibility  of  escape. 
But  now  gun-cotton  will  exert  itself,  and  put  forth  more  than 
what  was  believed  to  be  its  full  strength,  whether  it  see  any 
work  to  do  or  not.  It  will  behave  as  less  coy  explosives  have 
behaved  before  it — always  with  this  difference,  that  it  is  half-a- 
dozen  times  as  powerful  as  any  of  its  rivals,  with  the  exception 
