known,  their  solutions  quickly  become  covered  with  mould  in  warm
weather.  Reinsch  *  states  that  '028  per  cent,  of  tartaric  acid  in  water
"  began  to  diminish  the  bacteria,  and  0'2  per  cent,  killed  them."

Patent  No.  1,297, 1893,  proposes  the  use  of  tartaric  acid  for  purifying
water,  and  a  filter  has  been  devised  to  carry  out  this  idea.  Many
patents  use  tartaric  and  malic  acids  to  increase  the  solubility  of  boric
acid  and  borax  {q.v.,  p.  102) ;  it  would  seem  as  if  they  would  rather
diminish  the  eflficiency  by  providing  nutrient  material,  as  exemplified
by  Pasteur's  solution,  which  is  used  for  growing  organisms.
Oxalic  Acid  is  an  irritant  and  corrosive  poison,  and  is  said  to  be
antiseptic.  Its  solutions  certainly  do  not  develop  organisms;  even  the
oxalates  only  allow  their  growth  slowly.  But  in  practice  they  are
inapplicable.     Succinic  acid  is  slightly  antiseptic.
CHAPTER    XII.
PEACTICAL    METHODS.
Towns  :  Limited  Areas — Administration.  Sewers  and  Drains  :  Ashpits  and
Dust-Holes.  Houses  :  Walls  and  Wall  Papers — Furniture  and  Wood  Work
— Sinks.  Sick  Rooms  :  Isolation — Clothing — Excreta — Removal — Light  and
Air  —  Spray  —  After- Disinfection  —  Phenol  —  Sulphurous  Acid  —  Chlorine —
Liquid  Disinfectants  by  Spraying — Hot  Solutions — Cisterns — Water-Closets
— Earth-Closets — Middens — Cesspools — Infection  by  Flies — Automatic  Dis-
tributor— Wood  Paving — Urinals — "Urinal  Cakes"— Stables — Pigstyes  and
Cowsheds — Cattle  Markets  and  Fairs — Slaughter-Houses — Dairies — Bake-
houses— Pigeon  and  Fowl  Houses — Rabbit  Hutches— Cats  and  Dogs — Vehicles
— Skins,  Furs,  Wool,  and  Hair — Rags.  Disinfection  of  Air :  Impurities —
Sewer  Gas  —  Vaporisers  and  Filters  for  Air  —  Water  and  its  Purification.
Preservation  of  Timber  :  Copper  Sulphate — Creosote  Oils.
