^^$1^™'}    Koch's  Lymph  and  its  Dilutions.  169 
attention  to  medication  with  micro-organisms  and  their  products 
and,  for  that  reason  alone,  it  is  most  valuable.  Whether  it  will  be 
of  permanent  service  in  relieving  tuberculous  conditions,  time  and 
trial  only  can  tell.  Its  best  field  of  usefulness  seems  to  be  in  lupus 
and  in  the  early  stage  gf  tuberculoses.  In  the  advanced  stages  it  is 
positively  contra-indicated,  as  is  also,  in  the  opinion  of  some  physi- 
cians, its  use  as  a  means  of  diagnosis. 
The  word  "  lymph "  is  a  misnomer.  It  does  not  stand  (in 
this  connection  at  least)  for  the  lymphatic  fluid  of  the  body,  as 
might  be  supposed.  It  is  a  reddish-brown,  viscid,  glycerin-and- 
water  solution  ;  having  a  heavy  narcotic  odor,  somewhat  resembling 
that  of  opium,  miscible  with  water  in  all  proportions ;  neutral  in 
reaction  ;  reasonably  permanent  on  exposure  to  air;  sp.  gr.1-  1-150; 
and,  in  stronger  solutions,  becomes  turbid  upon  the  addition  of 
alcohol. 
With  a  neutral  10  per  cent,  solution,  neither  mercuric  chloride, 
potassio-mercuric  iodide,  nor  iodine  and  potassium  iodide  gave  any 
precipitates,  platinic  chloride  gave  a  yellow  precipitate ;  silver 
nitrate  gave  a  white  precipitate,  which,  on  boiling  with  strong 
nitric  acid  was  partially  dissolved  ;  leaving  a  whitish  residue  entirely 
soluble  in  AmHO,  and  a  yellow  solution;  barium  chloride,  and 
ferric  chloride  exerted  no  change ;  Fehling's  solution  showed  no 
evidence  of  glucose,  but  its  addition  gave  the  pure  violet  reaction 
of  albuminoids  (which  will  be  referred  to  later) ;  lead  oxyacetate 
solution  gave  a  white  precipitate  soluble  in  excess ;  the  flame  test 
revealed  sodium  and  not  potassium. 
If,  however,  following  L.  Reuter,2  we  use  a  slightly  acid  (HC\)  10 
per  cent,  solution  of  the  lymph,  we  get  a  heavy  reddish-brown  pre- 
cipitate with  iodine  and  iodide  of  potassium  ;  likewise  a  precipitate 
with  platinic  chloride,  and  a  faint  one  with  potassio-mercuric 
iodide.  Mercuric  chloride  causes  no  precipitation.  Ferrous  sul- 
phate solution,  slightly  acidulated  with  H2SOt,  yielded  no  precipitate 
on  standing,  indicating  the  absence  of  gold  salts.  This  experiment 
was  subsequently  confirmed  by  adding  auric  chloride  to  the  neutral 
solution,  as  well  as  to  the  acid.  In  both  cases  precipitates  were 
formed. 
1  My  experiment  confirms  the  figures  of  Mr.  Henry  Campbell,  in  Brit.  Med. 
Jour.  1 89 1,  76.— J.  W.  E. 
2  Pharm.  Ztg.,  1890,  747,  vide  A.  J.  P.,  1891,  19. 
