ON  PYROXYLIN. 
225 
From  these  results  we  may  conclude  that  both  kinds  have  the 
same  ballistic  force. 
In  these  experiments  the  gun  was  filled  to  the  height  of 
0-05m.  It  was  proposed  to  ram  it  harder,  reducing  the  height 
to  0-03m  ;  but  the  first  charge  fired  by  this  method,  and  with 
three  grammes  of  General  Lenk's  pyroxylin,  burst  the  gun 
barrel. 
This  accident  has  also  happened  in  firing  charges  of  the 
Bouchet  pyroxylin,  showing  the  resemblance  between  the  ex- 
plosive property  of  the  French  and  Austrian  pyroxyles. 
We  will  not  here  describe  all  the  attempts  made  by  the 
Commission  of  1846  to  obviate  the  inconvenience  arising  from 
the  too  rapid  combustion  of  pyroxylin,  but  will  confine  ourselves 
to  those  made  for  the  same  purpose  by  General  Lenk. 
He  first  unsuccessfully  tried  compressed  cartridges,  then 
some  which  he  called  long  cartridges,  formed  of  paper  cylin- 
ders covered  with  gun-cotton  yarn.  With  these  an  Austrian 
12-pounder  charged  with  about  481  grammes  of  gun-cotton  gave 
a  velocity  of  427  metres. 
But  this  speed,  though  the  greatest  attained  by  the  experi- 
ments in  question,  is  less  than  that  obtained  in  France  with  a 
similar  gun,  and  with  a  charge  of  2  kilogrammes  of  ordinary 
powder,  which  was  about  480  metres,  and  which  the  Commission 
of  1846  endeavored  to  attain  by  using  667  grammes  of  pyroxy- 
lin. 
Now,  it  has  not  been  proved  that  Lenk's  cartridges  would 
not  injure  pieces  of  ordnance  were  the  quantity  of  pyroxylin 
increased  so  as  to  obtain  the  same  speed  as  in  France. 
The  author  of  one  of  the  Austrian  reports  recognizes  the  fact 
that  the  results  obtained  are  unsatisfactory,  and  that  the  me- 
chanical means  employed  to  prevent  the  development  of  the  in- 
jurious properties  of  the  pyroxylin  neutralise  part  of  its  propel- 
ling power  ;  and  arrives  at  the  conclusion  that  the  problem  will 
be  resolved  only  when  firearms  are  made  in  which  the  injurious 
effect  may  be  disregarded.  This  is  also  our  opinion  ;  but  how 
to  overcome  the  objection  of  the  spontaneous  explosions,  which 
to  us  is  the  first  consideration  ? 
The  result  of  our  researches  is,  that  though  the  composition, 
method  of  production,  and  chemical  properties  of  pyroxylin  may 
15 
