Scrophulous people possess a peculiar constitution, and may therefore be said to constitute, in one respect, a distinct variety of the human race. This state is produced by a peculiar condition of the semen (owing to the peculiarity of the system which forms it), or of the female organs of generation, which possess the same general nature with the body, of which they form a part. When the organs of generation in both sexes are healthy, that is to say, similar in nature to what may be considered as the proper nature of the human race, taken as a distinct class of animals, then the semen stimulates the ovarium to the formation of a healthy child, or one which possesses a constitution, or susceptibility of performing, and having actions induced in it, similar to that of the majority of mankind. In this process, the ovarium is to be considered as a gland, and the semen as its peculiar stimulus. If, however, either the nature of the gland, or of its stimulus be changed, it is evident that the action induced must be more or less modified, and the secretion or product changed to a greater or less degree in its nature and properties. Were it possible for a progeny to be produced by an intercourse betwixt the human and the brute creation, they would possess a nature different from both, or perform actions of a mixed kind. This may be observed with regard to mules amongst brutes. In the same way, a healthy and scrophulous person must produce a child which differs from a healthy one, in having a certain peculiarity of constitution. Agents produce different effects in different animals; thus the matter of cow-pox applied to the cow and to man produce very different appearances. Agents likewise, in the same genus of animals, produce different effects, according to the peculiar constitution of the individual. Thus, the matter of small-pox in some men produces only a slight local sore, whilst in the generality it produces a general disease, and eruption. The same disease affords an instance of changes taking place in the constitution after birth, by the establishment of certain actions; for it is rendered unsusceptible of the same action being induced afterwards; and, in this respect, is brought to resemble the constitution of a different genus of animals, with regard to that disease. There are some constitutions, such as those called irritable, in which certain symptoms of febrile, and other actions, are much more violent than in people of a different description. In them, for instance, typhus fever is attended with a very frequent pulse, and yet the other effects of this action are not violent in the same proportion.