:greater_than_or_equal_to => -90, :less_than_or_equal_to => 90
validates_numericality_of :longitude, :allow_nil => true,
:greater_than_or_equal_to => -180, :less_than_or_equal_to => 180
:greater_than_or_equal_to => -90, :less_than_or_equal_to => 90
validates_numericality_of :longitude, :allow_nil => true,
:greater_than_or_equal_to => -180, :less_than_or_equal_to => 180