Proceedings, &c., 1867. 329 
Mr. Newbery said, if the filter did not possess that quality, it 
came very close to it. He intended to make further experiments 
and report hereafter. 
Professor Halford drew attention to the importance of the subject 
from another point of view. Disease and death had been produced 
by the introduction of microscopical animal organism; and it was 
of vast importance if this filter could separate such matter, render- 
ing the water wholesome. 
Mr. Dahlke (replying to the President, Mr. A. K. Smith, and 
others) said, that to render the filter available for household pur- 
poses, he proposed to attach it to the supply-pipe divided into two 
compartments, the first for arresting all the grosser impurities, while 
the second would form the real filter. The filtering material would 
ultimately wear out; but he had made apparatus for the General 
Post Office, London, at a cost of five guineas, which lasted five 
years. Mr. Dahlke further stated that a tank to filter 10,000 
gallons per day could be erected on stations, say at a cost of £50 
for filtering material ; brickwork and his own travelling expenses of 
course to be added. 
Mr. Newbery made several experiments with a small filter, using 
salt, and subsequently Sulphide of Ammonium. The filter in use 
was but just completed, and Mr. Dahlke stated that at least four 
and twenty hours should elapse from its being finished before being 
subject to any test. The mixture of salt and water left a slight 
brackish taste, and the Sulphide of Ammonia came out perfectly 
clean and free from smell. 
The President briefly called the attention of the members to the 
importance of the subject. 
Nominations for office-bearers for 1868, and to fill vacancies in 
Council, were then made. 
