5o 
Progress  of  Microbiology. 
<  Am.  Jour.  Pharm. 
\    January,  1921. 
the  best  method  of  harvesting  is  to  cut  the  whole  plant  back  to  near 
the  crown  when  18  months  old,  and  thereafter  annually,  cutting 
each  season  a  little  above  the  previous  year's  cut.  By  this  method 
a  harvest  is  obtained  every  year,  and  the  yield  should  gradually 
increase.  It  would  be  necessary,  however,  to  allow  a  number  of 
plants  to  grow  on  and  flower,  in  order  to  obtain  seed  for  the  renewal 
or  extension  of  the  plantation.  The  yield  of  dry  leaves  from  a  row 
of  80  yards  long,  cut  in  May,  1918 — that  is,  when  the  plants  were 
about  two  years  old — was  8>4  lbs.  With  rows  four  feet  apart  this 
is  equivalent  to  a  yield  of  about  400  lbs.  per  acre.  It  is  stated  that 
the  growth  of  the  plants  subsequent  to  being  cut  back  was  entirely 
satisfactory,  and  none  of  them  died.  The  results  obtained  in  the 
experiments  at  Kirstenbosch  indicate  that  under  suitable  conditions 
the  commercial  cultivation  of  buchu  should  prove  a  success.  B. 
betulina,  the  most  valuable  kind,  alone  should  be  grown.  The 
plant  is  particularly  adapted  to  dry  conditions,  and  may  be  culti- 
vated on  sunny  hillsides,  where  other  crops  will  not  succeed. 
THE  PROGRESS  OF  MICROBIOLOGY  * 
In  common  with  all  the  natural  sciences,  microbiology  passed 
through  an  empirical  stage.  For  it  is  only  in  mythology  that  Minerva 
springs  forth  a  finished  product  from  the  brow  of  Jove.  Jenner's 
discovery  of  vaccination  as  a  prophylactic  for  small-pox  was  an 
inference  from  a  fact  of  observation — namely,,  that  persons  who 
had  once  been  infected  with  cow-pox  seemed  to  enjoy  immunity 
from  small-pox.  Neither  Jenner  nor  his  immediate  successors 
reached  any  rationale  of  the  process  by  which  this  protection  is 
effected.  It  was  not  until  Pasteur  and  his  school  demonstrated  the 
casual  relationship  between  the  specific  living  organisms  and  disease, 
that  microbiology  became  entitled  to  rank  as  a  science,  and  the  ground 
was  clear  for  the  introduction  of  sero-therapy  and  vaccine-therapy 
which  have  since  made  such  rapid  strides  as  scientific  methods  for 
the  prevention  and  cure  of  disease.  According  to  Metchnikoff's 
theory  of  phagocytosis,  the  white  blood  corpuscles  are  engaged  in  a 
perpetual  campaign  against  the  microbic  invaders  of  the  blood- 
stream, which  if  not  destroyed  or  rendered  innocuous  may  do  dire 
*  From  The  Phar  n.  Jour,  and  Pharmacist,  Sept.  4,  1920. 
