A CLASSIFICATION OF THE MICRO-ORGANISMS 
FOUND IN WATER* 
By RUBERT W. BOYCE, M.B., Profkssor of Pathology, Univi rsity Collegk LiVKRpooi. 
CHARLES A. HILL, M.B., B.C., B.A. Cant\b., Assistant Bactkriologist, Univkrsity 
Collegk Lumirpool 
From the Pathological Laboratory, University College Liverpool. 
The following are briefly the results we have obtained from a year's constant examination 
of the Liverpool waters. The conclusions we iiave arrived at tend largely to support those arrived 
at by Professor Marshall Ward in his fifth report to the Water Research Committee of the 
Royal Society. Our observations are based upon 400 analyses. 
The sources of the waters examined are the following : — (i) The Streams and Lakes of 
the Watershed ; (2) the water of the Reservoirs before filtration ; (3) the water of the Reservoirs 
after filtration ; (4) the water in tlie Mains and Service Reservoirs ; (5) the water in the Dead 
Ends ; (6) the water in the Wells ; (7) the bacteria present in the Sand of the filter beds. 
The water has always been collected in small sterilized bottles, or in vacuum bulbs, which 
have been broken under the surface of the water. Plate cultures on gelatine and agar-agar were 
made as soon after collection as possible, and in most cases on the spot. 
Photographs were prepared of all the characteristic plate cultures, and it is hoped these may 
serve to aid in the more rapid identification of colonies. The photographs showed clearly that 
different bacterial floras exist for different localities. 
Results 
1. Wat 67- in Rivulets of Watershed. — There is a marked preponderance of the Bacillus 
fluorescens liquefaciens. 
2. Water of Reservoirs before filtration. — There are considerable numbers of liquefying 
bacilli, namely, B. fluorescens liquefaciens, B. luteus liquefaciens, and the Proteus group. 
3. Water of Reservoirs itnmecliately after filtration. — There is a marked elimination of 
the liquefying forms ; the chief forms present being exceedingly slow-growing forms, and consisting 
of non-liquefying cocci and bacilli, chromogenic and non-chromogenic. It is probable that many 
of these forms are derived from the sand in tlie process of filtration, and are more especially water 
bacteria. 
* Reprinted from the 'Journal of Pathology ami Bacteriology,' May, uSgg. 
