Page:Popular Science Monthly Volume 42.djvu/237

Rh birthright, make her a more worthy co-operator with her husband; a stronger spiritual sympathizer; one who will not flinch when confronted with the privilege of making noble women of her daughters, of saving her sons from falling victims to the sin which is dragging down to ruin so many of our finest young men?

"The height of the pinnacle" says Emerson, "depends upon the breadth of the base." Give, then, to our young women this broad basis of knowledge, as you wish the height attainable to be proportionate and exalted.

 

T would be difficult to say where the idea first originated of the possibility of artificially producing occult changes in the organism of a healthy individual, so that, if exposed to a contagious or an infectious disease, there would be an acquired resistance that would prevent the development of such a disease. Tradition states that, in the case of small-pox, the custom existed in South Wales of rubbing matter from the pustules of a small-pox patient on the skin of a healthy person's arm, in order to protect the latter individual from acquiring that malady; and, for a similar purpose, it was the custom in the Scottish Highlands to wind about the wrists of children worsted threads that had been moistened with such matter. Inoculation of healthy persons with variolous matter had long been practiced in Oriental countries when Lady Mary Wortley Montagu introduced it into England. And as recently as our civil war this procedure has been employed, because the usually mild attack of small-pox following the inoculation is less dangerous than the ordinarily acquired form of that disease.

The discovery of the protection afforded by vaccination suggested new working theories; for it was as remarkable that the contagious principle of small-pox should undergo some modification in the human system as it was that it was decidedly modified in the cow. It has been demonstrated by many experimenters that, in a calf that has not had cow-pox, inoculation of small-pox virus will cause that disease; and, furthermore, that matter from the eruption on the calf's udder will, if inoculated in an unvaccinnated person, produce the well-known phenomena of vaccinia. Science, accordingly, learned two facts from this: that the virus of a disease may be diminished, or attenuated, in its development in an animal organism other than that in which it found its most poisonous growth; and that this attenuated virus, introduced into