AN AUTOMATIC HOUSEHOLD FILTER. 
A Paper read before the Royal Society of Queensland, 
on June 27th, 1907. 
By J. BROWNLIE HENDERSCON, F.IC., 
(GOVERNMENT ANALYST), 
and H. WASTENEYS, F.CS., 
(Anatyst To THE BrispanE Board oF WATERWORKS.) 
Owi1ne to the water supply of Brisbane being delivered in 
an unfiltered state, and to its being at times of drought or 
flood undrinkable and exceedingly dirty, an attempt was 
made at the house of one of us (Mr. Henderson), to establish 
an automatic filter for the filtration of the water, which 
is delivered there from the Brisbane River supply. A 
similar filter had been found to give very good results with 
the “soft”? Enoggera supply at the Reservoir, but this 
was the first attempt to treat the “ hard” Brisbane River 
water by this method. 
A corrugated galvamzed-iron tank was made as in 
the diagrammatic sketch, with outlet pipe for the filtered 
water, wash out pipe with cock at the bottom, draw-off 
pipe with cock at the centre to run off water when cleaning 
top sand, and overflow, in case of flooding, at the top, the 
three latter openings being connected to the waste discharge. 
A perforated galvanized-iron pipe, three inches in diameter, 
was put down for the underdrain, and over this there was 
carefully packed washed gravel and sand as per sketch, 
to constitute the filter. The sand reached up to the level 
of the draw-off cock. A float in this filter was connected 
by a cord running over two pulleys to a swing arm attached 
to the outlet pipe, and to the storage tank pipes by barrel 
unions, as shown in sketch. To prevent syphon action, 
