782 
Normal  Salt  Solution. 
Am.  Jour.  Pharm. 
Nov.,  1918. 
specificity  of  an  antitoxin  is  determined  by  the  physical  condition  of 
its  colloid  particles  and  only  the  physical  condition  of  an  antitoxin 
distinguishes  it  from  normal  globulins.  In  some  cases  globulins 
may  combine  with  toxins  by  means  of  heat  alone.  Thus  if  the  toxin 
of  certain  staphylococci  is  heated  with  rabbit  serum  at  6o°,  the 
globulin  is  converted  into  an  antitoxin,132  but  usually  this  requires  a 
catalytic  agent.  Diphtheria  antitoxin  is  claimed  to  have  been  made 
from  normal  horse  serum  or  globulin  of  eggs  by  means  of  a  catalist 
(NaCl)133  but  this  work  has  not  been  corroborated  and  as  yet  the 
question  of  the  chemical  nature  of  this  antitoxin  remains  unsettled. 
According  to  Berg  and  Reiser's  work  the  evidence  points  to  a  non- 
protein character  for  the  tetanus  antitoxin.134 
NORMAL  SALT  SOLUTION.1 
By  Louis  Gershenfeld,  P.D.,  B.Sc. 
The  term  "  normal "  has  been  and  is  most  frequently  applied  by 
the  chemist  and  pharmacist  to  solutions  which  contain  a  given  weight 
of  chemical  that  bears  a  direct  relationship  to  the  molecular  weight 
of  the  particular  substance.  The  same  term  is,  however,  used  more 
frequently  by  the  practitioner  and  medical  man,  when  the  psysiolog- 
Jcal  salt  solution  is  desired. 
Normal  or  physiological  salt  solution  was  first  used  by  anatomists 
as  a  means  of  preserving  fresh  tissue  for  histologic  examination,  its 
superiority  over  pure  water,  which  has  been  found  absolutely  un- 
satisfactory, having  been  early  recognized.  This  preparation  orig- 
inally and  until  recently  had  a  sodium  chloride  content  of  only  0.6 
per  cent.  Its  subsequent  adoption  by  physiologists  to  preserve  the 
normal  irritability  of  isolated  tissue  preparations  undergoing  inves- 
tigations, and  its  wide  employment  in  the  physiologic  laboratory  in 
practically  the  same  saline  concentration  as  that  which  was  orig- 
inally used,  led  to  the  general  belief  and  acceptance  for  a  number 
of  years  that  such  a  solution  is  the  physiologic  salt  solution. 
132  Ostromisslenski. 
133  Ostromisslenski. 
is*  Berg,  W.  N.,  and  Kelser,  R.  A.,  Journ.  Agric.  Res.,  1918,  Vol.  13,  p.  471 
1  Presented  -at  the  meeting  of  the  Pennsylvania  Pharmaceutical  Associa 
tion,  Wilkesbarre,  Pa.,  June,  1918.' 
