^3  Our  Canaries 
chips  ;  beat  these  down  flat,  and  cover  all  over  with  a  layer  of  concrete  an  inch  in 
thickness,  and  no  rat  or  mouse  will  ever  penetrate  it. 
A  SERVICEABLE  ROOF. 
In  all  cases  where  a  wooden  roof  is  employed  in  an  exposed  position, 
particularly  if  this  is  of  light  boards,  a  second  layer  of  timber  super-imposed  over 
this  at  a  distance  of  about  three-quarters  of  an  inch  or  one  inch,  would  make 
a  vast  improvement,  and  not  only  form  a  protection  to  the  real  roof,  but  will 
indirectly  make  a  great  improvement  in  the  room  itself  by  keeping  it  cooler  in  the 
hottest  part  of  summer,  and  the  temperature  more  equable  at  all  times.    By  this, 
of  course,  is  meant  that  the  superstructure  should  be  supported  by  strips  of  lath 
nailed  down  to  the  roof  at  each  end,  with  an  extra  similar  support  at  a  distance 
of  about  eighteen  inches  across  the  full  width  of  the  roof.    Thus  there  will  exist 
an  air-space  of  the  thickness  of  the  supports  used  between  the  two  roofs,  and  the 
existence  of  this  space,  providing  an  egress  is  left  at  the  top,  as  there  should  be, 
will  cause  a  current  of  cool  air  to  be  always  circulating  between  the  two  layers  of 
wood  when  a  hot  sun  beats  fiercely  upon  the  top,  and  the  atmosphere  in  the  house 
itself  escapes  being  overheated. 
Where  this  is  not  considered  expedient,  the  existing  roof  of  wood  should  be 
well  tarred,  and  then  covered  with  a  layer  of  roofing  felt.  Two  or  three  coats  of 
tar  should  next  be  given  the  upper  surface  of  the  felt.  Each  coat  should  be 
allowed  to  become  dry  before  another  is  applied.  This  will  ensure  the  roof  being 
waterproof  for  some  months,  and  if  care  is  taken  to  repeat  the  tarring  once  or 
twice  a  year,  and  a  gutter  made  and  kept  in  good  order  along  the  eaves,  it  will 
form  a  most  useful  roof  permanently,  and  the  tarring  will  do  some  little  to  keep 
the  roof  cool  during  the  sultry  weather.  The  plan  of  tarring  and  felting  the  top 
surface  will  also  prove  most  advantageous  in  cases  where  a  double  roof  is  con- 
structed. It  costs  comparatively  little,  and  its  advantages  are  so  great  that  it  is 
very  advisable  to  carry  it  out  in  all  cases. 
DISPEL  THE  GLOOM. 
Efficient  lighting  is  another  important  feature  which  must  not  be  overlooked. 
As  will  be  obvious,  it  is  a  point  which  is  very  largely  controlled  by  site  and  locality. 
In  all  cases  the  interior  of  the  building  should  be  quite  as  well  lighted  and  as 
bright  as  any  ordinary  living-room,  so  that  the  birds  can  see  to  move  about  and 
feed  with  perfect  freedom  right  up  to  the  hour  of  sunset  at  least,  and  this  in 
ordinary  conditions  of  weather  in  autumn  or  spring.  It  goes  without  saying  that 
the  site  of  the  proposed  aviary  and  its  proximity  to  other  buildings,  will  very 
materially  affect  the  quantity  of  "  lights  "  or  size  of  windows  required  to  obtain 
this  result,  and  where  birds  are  to  be  kept  in  cages  instead  of  flying  loose,  a  rather 
stronger  light  will  be  necessary  in  the  room  to  ensure  the  cages  being  fairly  well 
lit,  even  if  they  are  arranged  on  the  side  opposite  the  window. 
