164 
Editorial. 
f  Am.  Jour.  Pharm. 
{      March,  1896. 
EDITORIAL. 
ROENTGEN'S  RAYS. 
Considerable  attention  has  recently  been  excited  in  scientific  circles  by  what 
is  popularly  designated  as  Roentgen' 's  Discovery. 
Professor  Wilhelm  Conrad  Roentgen,  of  Wurzburg,  Germany,  noticed  that 
the  light  of  an  induced  electric  current  in  a  Crookes'  tube  affected  a  photo- 
graphic plate  that  was  enclosed  between  two  wooden  slides.  In  other  words, 
he  found  a  light  capable  of  penetrating  wood.  He  immediately  instituted  a 
series  of  investigations  by  which  he  demonstrated  that  it  is  possible  to  photo- 
graph through  many  substances  that  are  opaque  to  ordinary  light ;  wood,  flesh, 
leather,  paper  and  certain  metals  are  the  most  conspicuous  substances  which 
he  found  to  be  transparent  to  these  rays. 
These  phenomena  have  since  been  investigated  by  a  number  of  other  physi- 
cists, and  Roentgen's  observations  have  been  confirmed. 
'  Mr.  Campbell  Swinton,  in  London,  demonstrated  that,  among  the  metals, 
aluminum  is  especially  transparent  to  these  new  rays.  He  placed  two  alumi- 
num trays  between  the  source  of  these  rays  and  a  photographic  plate;  one  of 
the  trays  contained  a  solution  of  alum  and  the  other  a  solution  of  iodine  in 
carbon  disulphide.  It  is  known  that  alum  solution  absorbs  ultra-red,  and 
iodine  solution  ultra-violet  rays  of  light.  The  conclusion  reached  by  Mr. 
Swinton  was  that  the  new  light  contains  rays  which  are  absorbable  by  iodin^, 
and  it  is  probable  that  they  are  ultra-violet  rays. 
In  this  country,  Professor  Wright,  of  Yale  University,  found  that  with  many 
substances  strong  impressions  were  obtained  upon  a  photographic  plate  even 
when  it  was  enclosed  in  an  opaque  wrapping  of  black  paper  and  covered  with 
a  piece  of  pine  board  one-half  inch  in  thickness. 
One  of  the  most  peculiar  observations  made  on  this  light  is  that  glass  is 
more  opaque  than  many  of  the  metals,  while  ebonite,  which  is  practically 
opaque  to  ordinary  light,  is  transparent  to  the  new  rays. 
The  term  X-rays  has  been  provisionally  applied  to  this  new  form  of  energy. 
On  another  page  we  give  the  results  of  some  experiments  by  Professor  E.  S. 
Bastin,  of  the  Philadelphia  College  of  Pharmacy,  on  the  presence  of  these,  or 
similar,  rays  in  sunlight.  His  experiments  were  made  on  the  17th  of  February, 
and  we  believe  he  is  among  the  first  to  announce  positive  results  from  sunlight, 
although  so  rapidly  is  the  study  of  Roentgen's  discovery  progressing,  he  may 
be  anticipated  by  some  one  else  before  his  paper  can  appear  in  print. 
It  is  too  soon  to  predict  the  uses  to  which  these  X-rays  may  be  applied,  but 
it  is  already  evident  that  the  bones  in  the  living  subject  may  be  examined  by 
them,  since  flesh  is  transparent  to  them,  while  bone  is  opaque.  No  doubt  the 
discovery  will  be  of  some  use  in  surgery;  in  fact,  it  is  claimed  that  a  number  of 
successful  operations  have  already  been  performed  in  which  foreign  bodies 
have  been  first  located  by  the  aid  of  these  rays.  In  Berlin  the  photograph  of  a 
man's  hand  revealed  the  presence  of  a  piece  of  glass  that  had  been  imbedded 
in  the  flesh  for  years.  Defects  in  metal  castings  may  be  detected  by  this  light; 
hence,  it  is  thought  it  will  be  especially  of  service  to  indicate  flaws  in  large  guns. 
Professor  Bastin  hopes  to  study  the  structure  of  living  plants  by  these  rays, 
if  he  is  so  fortunate  as  to  find  that  some  tissues  are  opaque  while  others  are 
transparent. 
