SECT. 2] TO THE RENAISSANCE 117 



same nature, and adduces the fact that "in cooking the white hardens 

 first, whether the egg be boiled or poached, but the yolk hardens 

 also if the heat is more", comparing the heat of the kitchen to the 

 innate heat of the chick. "But you will say", he goes on, "if the 

 albumen and the yolk are the food of the chick in the egg, what 

 then must we decide the material of the chick to be, since we have 

 already said that the semen is not present in the eggs. You will 

 find this material from an enumeration of the parts of the egg — there 

 remains only the shell, the two membranes, and the chalazae; — 

 nobody will assign the membranes or the shell as the material of 

 the chick, therefore the chalazae alone are the fitting substance out 

 of which it can be made." Having discovered this truth by the 

 infallible processes of logic, Fabricius brings all kinds of arguments 

 forward to support it; he adduces the three nodes in the chalazae 

 as the precursors of brain, heart, and liver; tadpoles, he thinks, 

 resemble significantly the chalazae, being "armless legless spines". 

 The eyes are transparent, so are the chalazae, therefore the latter 

 must give rise to the former. The liver is formed as soon as the heart 

 but is practically invisible as it does not palpitate. One of his most 

 gratuitous errors was the suggestion, now newly introduced, that the 

 heart (and other organs) of the foetus has no proper function, no 

 munus publicum, but beats only in order to preserve its own life. 

 Then there is a considerable section called De Ovorum utilitatibus, 

 which almost does for the hen's egg what Galen's De Usu Partium 

 did for the human body, and in which such questions as Why 

 the shell is hard and porous? and Why there are any membranes 

 in the egg? are taken up and answered with an elaborate display 

 of common sense. The influence of Galen is perceptible in a passage 

 about a liver-like substance being formed if blood is freshly shed into 

 hot water, in the usual terminology of formative faculties, and in the 

 division of fleshes into white and red, though the former is not 

 specifically derived fi"om the semen nor the latter from the menstrual 

 blood. The human placenta is described as cotyledonous, and need- 

 less confusion is caused by the doctrine that the "liquors, humours, 

 or rather, excrements, around the foetus, are two in number, sweat 

 and urine, the former in the amnios, the latter in the allantois". 

 But the drawings and illustrations of Fabricius' work are beautiful 

 and accurate — so much so, indeed, that it will always remain 

 a mystery how the man who figured the early stages of the 



