Dairying  in  Denmark.  159 
cent,  to  1 per  cent.,  but  occasionally  as  much  as  2 per  cent,  of 
the  mixture. 
Whichever  of  these  methods  is  employed,  it  is  quite  obvious 
that  the  germs  of  fermentation  have  a continued  relationship. 
In  other  words,  the  souring  material  of  to-day  is  a lineal  de- 
scendant of  that  used  yesterday,  that  of  the  day  before,  and  so 
on.  It  may  seem  strange  that  continual  “in-and-in  breeding” 
of  such  microscopic  organisms  should  act  prejudicially  upon 
the  quality  of  the  butter,  but  in  practice  this  is  found  to  be  the 
case,  so  in  well-managed  dairies  a new  stock  of  souring  material 
is  obtained  every  month,  by  letting  some  milk  or  cream  become 
sour  without  artificial  aid.  Indeed,  so  important  is  this  matter 
considered  that  a new  process  has  recently  been  advocated,  and 
is  now  being  tested  on  a large  number  of  the  best  farms.  A 
covered  can  is  filled  with  new  milk  and  warmed  up  to  104°  F. 
(32°  R.)  ; it  is  then  placed  in  a large  cubical  box  thickly  lined 
with  hay  (in  fact,  a rough  kind  of  Norwegian  oven),  and  locked 
up  ; at  the  end  of  24  hours,  when  required  for  use,  the  can  is 
taken  out,  and  it  is  found  that  the  milk  has  become  sour  and 
its  temperature  has  fallen  to  68°  F.  (16°  R.).  This  sour  milk  is 
then  used  to  sour  the  cream  which  will  be  churned  the  next 
day,  and  as  a fresh  supply  of  souring  material  is  made  daily  the 
danger  of  inherited  defects  is  removed. 
O 
The  souring  material  having  been  added  to  the  cream  in  a 
kind  of  barrel  with  a movable  lid,  through  a hole  in  which 
projects  the  handle  of  the  stirring-stick,  it  is  left  for  about  24 
hours,  being  occasionally  stirred  with  the  stick  without  remov- 
ing the  lid.  It  is  then  brought  to  the  requisite  temperature 
and  placed  in  the  invariable  upright  Holstein  churn. 
The  cream  is  generally  put  into  the  churn  at  a low  tempera- 
ture, 55°  F.  being  not  unusual,  and  57°  rarely,  if  ever,  exceeded. 
But  it  must  be  remembered  that  the  upright  Holstein  churn  is 
used,  and  that  this  machine  has  a very  small  dashboard  power  in 
comparison  with  its  size.  Therefore,  the  deficiency  in  power  is 
compensated  for  by  driving  the  dashboard  at  a high  speed, 
generally  between  120  and  150  revolutions  per  minute.  The 
consequence  is  that  when  the  butter  “ comes,”  which  it  does  in 
between  30  and  40  minutes,  the  temperature  has  increased  by 
4°  to  5°  F.,  making  it  at  the  finish  from  60°  to  62°  F.,  which 
is  quite  high  enough  to  ensure  the  production  of  good  butter, 
and  its  due  proportion  to  the  quantity  and  quality  of  the 
cream. 
Churning  is  stopped  when  the  butter-grains  are  no  larger  than 
grains  of  mustard-seed  ; in  fact,  as  soon  as  they  are  distinctly 
formed.  It  is  one  of  the  advantages  of  the  Holstein  churn  that 
by  means  of  a small  hole  in  the  top,  fitted  with  a sliding  lid, 
