Page:The Works of William Harvey (part 1 of 2).djvu/392

 it appears susceptible of powers, faculties, and accidents. Likewise, is it corporeal also ? for that which engenders mix- ture appears to be mixed : the progeny has a common re- semblance to the mother and father, and exhibits a doubtful nature when animals of dissimilar species, such as the pheasant and common fowl, engender ; that, too, appears to be corporeal which suffers from without, and to such an extent that not only are weakly embryos procreated, but even deformed and diseased ones, obnoxious to the vices as well as to the virtues of their progenitors.

With respect to these several particulars we may farther be permitted to doubt whether that which confers fecundity is en- gendered or accrues from without? Whether, to wit, it is transfused from the egg to the embryo and chick, from the hen to the egg, from the cock to the hen? For there appears to be something that is transferred or transfused, something, namely, which from the cock is transfused into the hen, and from her is given to the uterus, to the ovary, to the egg ; something which passing from the seed to the plant, is rendered again by the plant to the seed, and imparts fecundity. Because there is this common to all things which are perpetuated by generation, that they derive their origin from seed. But the semen, the conception, and the egg, are all of the same essential kind, and that which confers fertility on these is one and the same, or of like nature ; and this indeed is divine, the analogue of heaven, possessed of art, intel- ligence, foresight. This is plainly to be seen from its admira- ble operations, artifices, and wisdom, where nothing is vain, or inconsiderate, or accidental, but all conduces to some good end.

Of the general principles and science of this subject we shall treat more at length in the proper place ; we have now said as much incidentally as seems necessary, the occasion having pre- sented itself along with our consideration of the hen's egg, namely, how many things inhere which induce fertility, and how this is induced, and whether it is an affection, a habit, a power, or a faculty; whether it is to be regarded as a form and sub- stance, as a something contained generally, or only in some particular part since it is quite certain that a hypenemic egg is a perfect egg in so far as each sensible particular is concerned, and yet is barren ; the uterus in like manner, and the hen and the cock are all perfect ; yet are they severally sterile, as being