April 21, 1905.] 



SCIENCE. 



ism. Reservoirs are constantly receiving 

 water which is not always of a certain 

 standard; besides, the organic matter also 

 varies in amount. This alone would tend 

 to throw doubt on the value of sulphate of 

 copper in the disinfection of reservoir 

 water, notwithstanding the argument that 

 the water may be frequently tested to as- 

 certain its contents. It must be remem- 

 bered that we have before us for consid- 

 eration the use of copper in exceedingly 

 minute amounts which may be easily 

 neutralized and rendered useless by dif- 

 ferent constituents of the water. 



As a matter of fact, the disinfection of 

 reservoir water on the occurrence of an out- 

 break of typhoid fever is not the most im- 

 portant consideration. Our first duty 

 should be to ascertain the origin of infec- 

 tion, which is not in the reservoir itself, but 

 in some way connected with the reservoir 

 supply. The most exhaustive inspection is 

 frequently required to discover this con- 

 tamination, as it is commonly due to mild 

 or ambulant cases of typhoid fever which 

 have escaped detection or have been mis- 

 taken for some other disease. Until we 

 have accurately determined the origin of 

 infection or have used every effort to do 

 so, and if possible have isolated the cases, 

 have performed and maintained thorough 

 disinfection at the seat of infection, we have 

 not properly performed our duties as public 

 health officials. In these instances other 

 means of preventing the extension of ty- 

 phoid fever must of course be employed. 

 The character of these depends somewhat 

 on the conditions present in each outbreak, 

 and it is likely that in this connection the 

 sulphate of copper can be used advantage- 

 ously. Whatever future investigation may 

 disclose as to the value of this agent as a 

 disinfectant, I am certain that our present 

 knowledge of it does not justify us in de- 

 pending upon it in outbreaks of typhoid 



fever to the extent recommended by Dr. 

 Moore. 



Dr. Moore said: In concluding this dis- 

 cussion it does not seem necessary to make 

 any further reference to the efficiency of 

 copper sulphate and metallic copper. That 

 it really does all that is claimed for it at 

 tremendously high dilutions seems to have 

 been abundantly demonstrated both by 

 laboratory experiments of independent 

 workers and by its use in a praQtical way 

 upon a large scale. 



The one point about which there is nat- 

 urally the most question is the effect of 

 copper upon the human system. It is diffi- 

 cult for any of us to abandon any preju- 

 dice, whether it has any foundation in fact 

 or not, and to expect a universal acceptance 

 of the use of a metal which for years has 

 been looked upon with fear and distrust in 

 this country is out of the question. 



However, since there has been such a 

 unanimous expression of opinion from all 

 the speakers that they would unquestion- 

 ably prefer a copper-treated water to one 

 containing algae or typhoid or cholera 

 germs, it seems that it may be worth while 

 to use the few moments at my disposal in 

 an attempt to point out some of the facts 

 that are well known regarding the effect 

 of copper upon man. For, contrary to the 

 idea of some, we have a very large accumu- 

 lation of facts along this line, as the result 

 of experiment upon the lower animals as 

 well as man. 



Certainly, the argument that our daily 

 food naturally contains comparatively large 

 amounts of copper is not one in favor of 

 using the same substance in any quantity 

 for the purpose of adulteration or sophis- 

 tication. Nor was it intended that a refer- 

 ence to this fact should be so interpreted. 

 The only point that it seemed desirable to 

 make was that since we had such a tre- 

 mendous amount of practical evidence, all 

 tending to demonstrate the harmlessness of 



