Report  on  Implements  at  York. 
589 
cold  air,  whilst  the  ventilation  above  the  ceiling,  aided  by  the 
radiation  of  the  air  by  the  hot-water  pipes,  secured  a constant 
current.  Having  a supply  of  water,  Mr.  Bradford,  to  improve 
the  process,  made  a stream  to  flow  through  the  ventilating  pipes, 
but  this  is  not  a necessary  feature  of  his  system.  At  the  top  of 
the  building  was  fitted  a “Walness”  ventilator  or  extractor. 
Mr.  Bradford  thus  describes  his  ventilating  arrangements : — 
“ The  Dairy  building  is  designed  and  constructed  with  a view  to 
its  internal  atmosphere  being  as  cool  and  as  pure  as  possible,  a 
constant  current  of  air  being  carried  through  it.  This  current 
is  created  by  means  of  a simple  and  efficient  ventilator  or 
No.  1. — Boiler  and  Hot  Water  Cistern. 
„ 2. — “Diaphragm  ” Churn. 
„ 3. — “ Albany  ” But  ter- Worker. 
„ 4. — Washing-Trough. 
No.  5. — Table. 
„ 6. — Ventilating  Chamber,  with  Slate  Top. 
„ 7. — Kevolving-Disc  Milk-Pan  Stands. 
„ 8. — Fresh  Air  Inlet. 
extractor,  called  the  Walness,  which  is  placed  in  the  roof,  and 
the  current  is  maintained  by  means  of  an  air-chamber  built  in 
and  upon  the  floor,  the  chamber  above  the  floor-level  being 
of  table  height,  with  sliding  air-bricks  built  in  the  side  and  end 
avails.  The  chamber  below  the  floor-level  being  an  excavation 
of  suitable  depth,  the  greater  the  depth  the  better.  The  fresh 
air  is  conveyed  into  the  bottom  of  the  chamber  by  means  of 
glazed  earthenware  pipes  carried  underground  any  required 
distance ; and  it  is  a noteworthy  feature  of  this  ventilating 
arrangement  that  wherever  a down-flow  of  water  in  these  pipes 
is  available,  a correspondingly  increased  up-current  of  cold  air 
