620 



SCIENCE. 



[N. S. Vol. XXI. No. 538. 



work which has been described by the pre- 

 vious speakers, nor do they detract in any 

 important degree from the usefulness of 

 this discovery. They are presented merely 

 to show that copper sulphate must be used 

 with discretion, and like all other good 

 things it may fail at critical times. 



Dr. A. H. Doty, health officer, port of 

 New York, said: As the result of my own 

 investigations with sulphate of copper, I 

 am convinced of its value in sanitation, 

 particularly as a deodorant and for the 

 clarification of water when used either 

 alone or in combination with lime. So far 

 as its germicidal value is concerned, I do 

 not believe that at present we are in pos- 

 session of sufficient data to present definite 

 and satisfactory information on the subject. 

 Tests which have already been made at the 

 New York State Quarantine Laboratory 

 with the typhoid and cholera organisms in 

 distilled water, tap water, contents of street 

 sewers and broth indicate that the germi- 

 cidal value of this agent may equal our 

 expectations. I have been interested in 

 Dr. Moore's valuable publication relative 

 to the purification of reservoir water by 

 copper sulphate. During the past summer 

 I witnessed practical demonstrations of 

 the value of this agent in the direction 

 just referred to, and have recently sug- 

 gested the use of it in a small reservoir in 

 the western part of New York, where the 

 water was so offensive by the reason of a 

 fishy odor and taste that it covdd hardly be 

 used for drinking purposes. The report of 

 the health officer who had the matter in 

 charge leaves no room for doubt as to the 

 successful result. Within a few days after 

 the introduction of the copper in accord- 

 ance with Dr. Moore's suggestion, the of-, 

 fensive odor and taste of the water had 

 disappeared and since that period there 

 have been no further complaints. In ex- 

 periments which were made during the past 

 summer with water containing mosquito 



larva? taken from pools in districts where 

 this insect was actively propagated and 

 placed in large wooden tanks, I found that 

 the copper alone and in combination with 

 lime promptly deodorized and clarified the 

 contents of these receptacles even when 

 large amounts of decomposed organic mat- 

 ter were added. However, in these in- 

 stances more copper was used, usually 

 from five to twelve grains for each gallon 

 of water experimented with. Even with 

 this amount, — chemical examination at the 

 end of twenty-four hours failed to detect 

 the presence of copper in the clarified 

 water. I am satisfied that Dr. Moore's 

 suggestions as to the use of copper in small 

 amounts for the destruction of algae, and 

 for removing the offensive odor and taste 

 which frequently occur in reservoirs, is safe, 

 practical, economical and very effective. 

 However, I am unable to endorse the recom- 

 mendation made by Dr. Moore as to the use 

 of sulphate of copper as a disinfectant in 

 reservoirs presumed to contain pathogenic 

 organisms, particularly the typhoid bacilli. 

 As a result of a sudden and formidable 

 outbreak of typhoid fever in a community, 

 and in the absence of some known cause, we 

 are justified in assuming that the water 

 supply, if a common one, is the medium of 

 infection, although we rarely have positive 

 proof of this as a result of bacteriological 

 examinations. There are but few instances 

 where the organism has been detected in 

 drinking w&ter. Therefore, if present we 

 can not as a rule determine when they dis- 

 appear. In this there is a great difference 

 between the satisfactory resi:lts obtained in 

 laboratory experiments where we know that 

 the bacilli are present, and know when they 

 are destroyed. Furthermore, in treating 

 the contents of a reservoir we are dealing 

 with factors which are not present in ex- 

 perimental work. For instance, the un- 

 certainty as to the exact character of the 

 media which presumably contain the organ- 



