It is universally found that the weights of two bases which neutralize the same weight of one acid are equivalent in their power of neutralizing other acids.
Its serum in course of time is found to contain something (antitoxin) which has the power of neutralizing the toxin secreted by the organism when parasitical upon the body.
Even in normal circumstances their play and counterplay, attractive and repellent, must be manifold almost beyond conception; for the body may be regarded as a collective organization consisting of a huge colony of micro-organisms become capable of a common life by common and mutual arrangement and differentiation of function, and by toleration and utilization of each other's peculiar products; some organs, such as the liver, for example, being credited with a special power of neutralizing poisons, whether generated under normal conditions or under abnormal, .which gain entrance from the intestinal tract.
Coincidently therewith, the hope of neutralizing infections by fortifying individual immunity has grown brighter, for it appears that immunity is not a very radical character, but one which, as in the case of vaccination, admits of modification and accurate adjustment in the individual, in no long time and by no very tedious methods.
Oxides of iron and manganese can only be used in glass manufacture in comparatively small quantities for the purpose of colouring or neutralizing colour in glass, and their introduction would not be a matter of sufficient importance to be specially recorded.