Second Report to the Royal Society Water Research 

 Committee. The Vitality and Virulence of Bacillus 

 anthracis and its Spores in Potable Waters. 



By Percy F. Frankland, Ph.D., B.Sc, F.R.S., Professor of Chemistry 

 in University College, Dundee, and H. Marshall Ward, D.Sc, 

 F.R.S., F.L.S., Professor of Botany, Royal Indian Engineering 

 College, Coopers Hill. Presented to the President and Council, 

 March 16, 1893. 



Introduction. 



In our First Report we endeavoured to give a concise account of 

 the more important work which has been done on the bacteriology of 

 water, and devoted special attention to those investigations which 

 have thrown any light on the vitality of pathogenic bacteria when 

 submerged in aqueous media of various kinds and under various cir- 

 cumstances. We showed what a very large amount of scientific labour 

 has already been bestowed on this comparatively new subject ; and 

 we as far as possible sifted this accumulated material, collecting those 

 facts which may be reasonably regarded as definitely proved, and 

 separating them from those which are more or less uncertain, proble- 

 matical, or contradictory. The results of this critical analysis we 

 embodied in a number of conclusions, to be found on pp. 124 — 219 of 

 our Report, and to which we would again refer the reader. 



In this summary and conclusions we have prominently pointed out 

 that the information which is at present most urgently required 

 from a practical point of view is with regard to the manner in which 

 the vitality of pathogenic bacteria is affected by the presence of non- 

 pathogenic or saprophytic forms. Although several investigators 

 have already approached this question, we were obliged to indicate 

 that their results have to be received with much caution, in conse- 

 quence of the great experimental difficulties which attach to this 

 inquiry, and which we were of opinion had not in some cases been 

 adequately taken into account to prevent misleading results being 

 obtained. 



