ABSTRACT
This chapter attempts to indicate the slow progress towards the light in the one hundred fifty to two hundred years preceding what may be called the Pasteurian period. This progress was on several lines: a differentiation of diseases one from another; an increasing realisation of the part played by overcrowding and dirt, whether of respiratory or excremental origin, in the production of communicable diseases; and varying efforts to prevent the spread of infection. Sanitary progress owes much to laymen without special scientific knowledge. The principal purpose and benefit of the establishment is to prevent any infectious fever from spreading through poor families, and through the town. The chapter finally concerns the science of preventive medicine and with the motives which led to its practice, not with an account of this practice; and from this standpoint it will suffice to set out the following dates without further attempt to dilate upon their social significance.
