The author describes and analyses the methods of disinfection in use until the end of the 18th century, i.e. before the scientific demonstration of the role of pathogenic microorganisms. These methods are classified into three categories: chemical (by derivatives of sulphur, mercury, copper, and also by alkalis and acids), physical (heating, fumigation, filtration, etc.) and biological (burial). The author concludes that, despite their empiricism, these methods were of great value to those responsible for controlling diseases of animals, as in some cases they were able to eradicate diseases while still ignorant of the causal mechanisms.