MICHIGAN ACADEMY OF SCIENCE. 177 



DISINFECTION BY MEANS OF FORMALDEHYDE AND POTAS- 

 SIUM PERMANGANATE. 



JAS. G. GUMMING. 



The use of disinfectants and antisejjtics as preservatives began at 

 a remote period of antiquity. It is quite evident that some of the agents, 

 which modern investigation has shown to be most effectual disinfectants, 

 were not unknown in the earliest periods to which our knowledge ex- 

 tends. We find that our most reliable antiseptics or preservatives, the 

 purified coal-tar comj^ounds contributed by modern chemistry to the art 

 of disinfection, were employed in a crude form by the Egyptian em- 

 balmers. Besides the coal-tar compounds, sulphur and its compounds 

 appear to have been frequently used by the ancients. It certainly Avas 

 in use in the time of Homer, for we find that Ulysses employed 

 burning sulphur to fumigate a palace, the inmates of which had been 

 slain. Here as in most of the historical references to sulphur at this 

 time, it had its place among religious ceremonies. Later history tells 

 of the practice o'f burning sulphur by the Italians for the prevention of 

 parasitic diseases of vines and about the same time skin diseases of 

 cattle were treated by the application of creasote. 



The empirical knowledge of the ancients has had a new^ birth in the 

 scientific discoveries of the present era. They knew that certain chem- 

 ical substances might be used as preservatives and that others were used 

 in parasitic diseases, but because the}' had no knowledge of the scientific 

 causation of putrefaction, fermentation and contageous and infectious 

 diseases, their application was limited and their results not always en- 

 couraging. The stimulus which has recently been imparted to the in- 

 vestigation of disinfectants is the discovery of microscopic life as being 

 the cause of infectious and contagious diseases. Until comparatively 

 recent times disinfection was based a purely chemical and physical 

 knoAvledge, but since Pasteur and others have made their important 

 discoveries the art of disinfection has been based on scientific principles. 



As late as 1860 disinfection was an obscure art, but since this date 

 new disinfectants have been discovered and the methods of using those 

 already known, at that time, have been so thoroughly investigated and 

 perfected, that severe epidemics have been practically unknown in civ- 

 ilized countries, during the last decade. 



Of the various disinfectants employed at the present time for room 

 disinfection formaldehyde is undoubtedly the most efficient. Three 

 methods of procuring it in its gaseous state are in quite common use; 

 the lamps which form formaldehyde by the partial oxidization of methyl 

 alcohol generally through the agency of platinum black; the distillation 

 of a solution of the gas in water ; and the sheet method, by this method 

 formaline is sprayed on suspended sheets from w^hich it evaporates and 

 diffuses throughout the surrounding space. 



Recently a new method of disinfection has been suggested by Henry 

 D. Evans and its practical application has been investigated by Dr. J. 

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