360  Scientific  and  Technical.  Abstracts.  {Am-^yi^rm' 
Evidence  in  regard  to  the  prophylactic  value  of  serum  is  meager. 
Certainly  it  confers  no  complete  or  durable  immunity.  As  a  thera- 
peutic agent,  however,  serum  seems  to  have  had  some  success. 
The  authors  regret  that  popular  and  professional  interest  should  t 
so  often  center  on  vaccines  and  serums  where  anti-rat  measures  are 
demanded.    If  people  want  to  be  vaccinated  for  plague,  let  them; 
but  the  important  thing  is  to  kill  the  rats. 
Toxic  Effects  of  Shaking  Arsphenamine  Solution. — That 
the  shaking  of  alkalinized  aqueous  solutions  of  arsphenamine  in  the 
air  for  60  or  even  30  seconds  greatly  increases  their  toxicity,  prob- 
ably by  oxidation,  is  stated  by  G.  B.  Roth  as  a  result  of  experiments 
described  by  him'  in  a  recent  report  to  the  U.  S.  Public  Health 
Service. 
Some  preparations,  of  neoarsphenamine  particularly,  may  be 
difficulty  soluble,  and  sUch  are  liable  to  be  shaken  to  hasten  solution. 
The  results  from  this  are  almost  always  highly  toxic  and  should 
not  be  used  clinically;  although  a  relatively  low-grade  preparation 
may  tolerate  5  or  10  seconds  of  shaking  and  yet  pass  the  Hygiene 
Laboratory  tests.  Shaking  in  a  closed  bottle  containing  no  air  seems 
not  to  increase  the  toxicity. 
The  author  concludes  that  the  toxicity  of  the  solutions  is  greatly 
influenced  by  the  manner  of  their  preparation,  and  that  they  should 
not  be  made  in  an  open  mortar  or  a  large  beaker. 
Fractionation  of  Chaulmoogra  Oil. — An  article  by  A.  L. 
Dean  and  Richard  Wrenshall,  just  reprinted  by  the  U.  S.  Public 
Health  Service  from  the  Journal  of  the  American  Chemical  Society, 
describes  experiments  made  at  the  University  of  Hawaii  into  the 
fractionation  of  chaulmoogra  oil.  The  hope  was  to  find  a  fraction 
that  contained  the  curative  principle  without  including  the  one  that 
renders  the  whole  oil  intolerant  to  many  patients. 
Four  lines  of  experimental  study  were  followed:  (1)  Separa- 
tion of  the  fatty  acids  by  crystallization  from  alcohol  was  tried  and 
abandoned  because  the  fractions  gave  low  melting  solids  and  oily 
mother  liquids.  (2)  Separation  by  means  of  barium  acetate  was 
abandoned  as  unsuitable  to  production  on  a  large  scale.   (3)  Frac- 
