Cur vertigo surgenti potius accidat quam sedenti? An quoniam quiescenti humor universus unum in membrum se colligit: ex quo cruda etiam ova nequeunt circunverti, sed protinus decidunt. Moventi autem humor se aeque expandit, etc. Aristot. in problemat. 6. 4. Si ovum filo circumligatum super igne aut candela accensa teneas, filum non comburetur, nisi forte post multum temporis, exudat enim humor, qui lineum filum humectat. idem linteo aridis vini fecibus circumvoluto accidit. Naturam vitellus ovi, et albumen habent contrariam, non tantum colore, verumetiam virtute. Vitellus enim spissatur frigore, (idem Niphus asserit:) albumen non, sed amplius humet. contra albumen spissatur igne, vitellus non, sed mollis persistit, nisi peruratur. magisque in aqua fervente, quam ad ignem cogitur, atque induratur. Membrana haec inter se discernuntur, Aristot.[1] Sic et Albertus, Vitellus ovi cum assatur, nisi comburatur, non durescit, sed mollitur potius sicut cera. Et quoniam mollescit dum calescit, corrumpitur facile collecto superfluo humore temporis vel loci, si aliquandiu immoretur. Albumen vero non facile congelatur frigore: sed humidius efficitur potius, et cum assatur durius: et in generatione pulli densatur in substantiam membrorum.

Why the dizziness arises in the person who gets up rather than in that who is seated? Perhaps because in that who is standing the whole humor gathers in only a part of the body: that's why also the raw eggs cannot turn over, but suddenly fall down. On the contrary in a moving person the humor is uniformly distributed etc., Aristotle in Problemata VI, 4. If you held on the fire or a candle an egg wound with thread, the thread won't burn, if not even after quite a lot of time, in fact the humor transpires and goes to moisten the flax thread. The same thing happens for a flax cloth that has been wound around dry dregs. The yolk of the egg and the albumen have an opposite composition, not only for the color but also for their properties. In fact the yolk with the cold becomes thick (Agostino Nifo reports the same words), the albumen no, but it becomes more damp. On the contrary the albumen thickens with fire, the yolk no, but it keeps soft, unless it is burnt. And it grows thick and hardens mostly in hot water than directly on fire. These two structures are separated each other by a membrane, Aristotle. Also Albertus is expressing himself in this way as follows: The yolk of the egg when roasted, if is not burnt, doesn't harden, on the contrary, it becomes squashy like wax. And since while getting warm it becomes soft, easily it changes in picking up the overabundance of damp of the climate and of the place if it stands for a certain time. But the egg white is not easily frozen by the cold: on the contrary, it becomes more damp, and when fried becomes harder: and during the development of the chick it grows thick into the substance constituting the parts of its body.

Et rursus eadem Aristoteles de generatione anim. 3. 2.[2] his verbis: Naturam candidum et luteum contrariam habent. luteum nanque gelu duratur et coit, calore contra humescit. quapropter cum vel in terra, vel per incubitum concoquitur, humescit, atque ita pro cibo animalibus nascentibus est. Nec vero cum ignitur assaturque quoniam naturae terrenae est, ut cera. ideoque cum plus iusto calescunt, nisi ex recremento humido sint, saniescunt  reddunturque urina. at candidum gelu non concrescit, sed magis humescit. ignitum solidescit. quamobrem cum ad generationem animalium concoquitur, crassescit. ex hoc enim consistit animal. ¶ Si quis rupto putamine ova plura in patinam conijcit excreta, et coquit igne molli et continente, vitelli omnes in medium coeunt: albumina autem circundant [circumdant], et se in oras constituunt, Aristot.[3] ¶ Candidum ex ovis admixtum calci vivae glutinat vitri fragmenta, vis vero tanta est (ovi candido, Hermol.) ut lignum perfusum ovo non ardeat, ac ne vestis quidem contacta aduratur, Plin.[4] Galenus in opere de simplicibus medic. ovorum albumen magis terrenum oleo esse scribit, et similem ei esse secundum humorem oculi. Albumen mixtum est e substantia aerea, terrea et aquea simul, sicut oleum: sed magis terrestre est quam oleum dulce, quare aegre concoquitur, Ant. Gazius.

And Aristotle in De generatione animalium III, 2 still says the same things by these words: The yellow and the white have opposed natures. In fact the yellow hardens in the cold and thickens, on the contrary liquefies with the heat. Therefore it liquefies when undergoes a concoction, both in earth and because of brooding, and in this way it becomes food for the animals when growing. But subjected to fire and cooking it doesn't harden because of earthy nature, like the wax. Insofar when they get warm more than due, unless are constituted by damp material of discard, they become viscous and are made unfertilized. The white, on the contrary, under the influence of the cold doesn't harden, but mostly liquefies. Submitted to the heat it becomes solid. Therefore it thickens when submitted to the concoction of the reproduction of the animals. In fact from it takes origin the animal. ¶ If after the shells have been broken one cooks on a low and continuous heat many eggs set down one by one in a pan, all the yolks gather towards the middle: for the albumens get themselves around and place themselves at the periphery. ¶ The white obtained from eggs mixed with quicklime joins the fragments of glass: in truth the strength in it is so great (in egg white, Ermolao Barbaro) that a wood piece sprinkled with egg doesn’t burn, and even a clothing smeared with it doesn’t catch fire, Pliny. Galen in De simplicium medicamentorum temperamentis et facultatibus writes that the white of the egg is earthier than the oil, and that the ocular liquid is in the second place for similarity. The albumen is a mixture of air, earth and water all together, as the oil: but it is earthier than the sweet oil, that's why it is barely digested, Antonio Gazio.

¶ Sexus ovorum. Quae oblonga sunt ova, et fastigio cacuminata, foeminam {a}edunt. quae autem rotundiora et parte sui acutiore obtusa, orbiculum habent, marem gignunt, Aristoteles[5]. eandem sententiam Albertus approbat: reprehendit vero translationem sui temporis tanquam contrariam iis verbis quae nunc recitavimus. Nostri quidem codices Graeci et Gazae translatio eam sententiam habent, quam nunc retuli, et Albertus comprobat. Avicenna scribit ex orbiculari ovo brevique progigni marem: ex oblongis acutisve foeminam. ipsum hoc comprobat experimentum et suffragatur ratio. siquidem virtutis perfectio in masculinis ovis ambit aequaliter, et continet extrema. at in foemininis, a centro longius abit materia in quo est vitalis calor. hoc vero plane imperfectionis argumentum est, Albertus ut citat Caelius. In ovis tam difficile saporum et sexus discrimen est, ut nihil gulae proceribus aeque incertum sit, Marcellus {Vergilius} <Virgilius>. qui cum Columellae et Aristotelis de sexu ovorum discernendo sententias contrarias recitasset: Est sane (inquit) in natura gravis author Aristoteles: Columella tamen villaticam pastionem ex quotidiana observatione et experientia docebat. nec nostrum est inter tam graves scriptores tantas componere lites. Video Plinium quoque cum Columella et Flacco sensisse. Quae oblonga sint (inquit) ova, gratioris saporis putat Horatius Flaccus. Foeminam {a}edunt quae rotundiora gignuntur, reliqua marem. Longa quibus facies ovis erit, illa memento, | Ut succi melioris, et ut magis alba rotundis | Ponere nanque [namque] marem cohibent callosa vitellum, Horatius lib. 2. Serm.[6] Cum quis volet quam plurimos mares excludere, longissima quaeque et acutissima ova subiiciet. et rursum cum foeminas, quam rotundissima, Columella[7]. Ex ovis, praesertim in plenilunio natis, si plenilunii tempore subijciantur incubanda, et ita observetur temporis ratio ut in plenilunio etiam pulli excludantur, omnibus foeminas non mares nasci, quidam apud nos arbitrantur.

¶ Sex of the eggs. The oblong and at apex pointed eggs generate a female. On the contrary those rather round and obtuse in correspondence of the sharp end, and having a circular aspect, generate a male, Aristotle. Albertus is agreeing with this affirmation: in fact he criticizes his contemporary translation as antithetical to these words I just reported. Really our Greek codes and the translation of Teodoro Gaza contain that affirmation I just reported and with which Albertus is agreeing. Avicenna writes that from a round and short egg a male is generated: a female from oblong and sharp ones. The experience proves just this and the reasoning bears out. In fact in masculine eggs the perfection of the force wraps up evenly, and contains the deeper portions. While in feminine eggs the matter goes away much more from the center, where the vital heat is located. This in fact is clearly a confirmation of imperfection, Albertus, as Lodovico Ricchieri quotes. In the eggs it is so difficult to discern the tastes and the sex that for gluttony's teachers nothing is equally uncertain, Marcellus Virgilius alias Marcello Virgilio Adriani. Who, after related the contrary opinions of Columella and Aristotle in distinguishing the sex of the eggs, so adds: To tell the truth, Aristotle as far as nature is concerned is an authoritative source: nevertheless Columella taught the breeding in farm founding himself on daily observation and experience. But it is not up to me to compose the enormous divergences existing among so authoritative writers. I see that also Pliny agreed with Columella and Horace. And he continues as follows: Horace believes that oblong eggs are of more pleasant taste. Those laid rounder produce a female, the other ones a male. Remember to put on the table the eggs with oblong appearance for their flavor is better, and are more rich in albumen than the round ones, for the shell contains a male yolk, Horace II book of Sermones. If someone wishes that very many males are hatched out, he will place under the hen all the longest and most pointed eggs. And if on the contrary he wishes females, the roundest ones, Columella. Some of ours believe that from the eggs, above all from those laid during full moon, if put under hens during full moon, and paying attention to calculate the time so that also the chicks hatch during full moon, from all of them females and not males are born.

de ovis monstrosis, ut geminis et mollibus, etc. de irritis
vel sterilibus, ut subventaneis. de corruptis, ut urinis, etc.

the monstrous eggs, as twin
and those with soft shell, etc.
Those not good or sterile, as those full of wind. Those rotten, as those full of wind, etc.

Ova gemina binis constant vitellis. qui ne invicem confundantur, facit in nonnullis praetenue quoddam septum albuminis medium. aliis vitelli contactu mutuo sine ullo discrimine iunguntur. Sunt in genere gallinarum, quae pariant gemina omnia, in quibus animadversum est, quod de vitello exposui. quaedam enim duodeviginti peperit gemina, exclusitque, praeterquam, si qua essent (ut fit) irrita. Caeteris itaque foetus prodiit, sed ita gemini excluduntur, ut alter sit maior, alter minor: et tandem in monstrum degeneret, qui minor novissime provenit, Aristot.[8] Quaedam gallinae omnia gemina ova pariunt, et geminos interdum excludunt, ut Cor. Celsus au<c>tor est: alterum maiorem, alioquin negant omnino geminos excludi, Plin.[9] Vetus quoque Aristotelis interpres (inquit Vvottonus) ad eundem sensum vertit ex Arabico ita: Et in quolibet inveniuntur gemelli, et unus gemellorum parvus est, et alter magnus: et multoties est parvus monstruosus.

Twin eggs are made up by two yolks. Which, in order to do not merge each other, in some eggs they give rise to like a very thin diaphragm of albumen in between. In other eggs the yolks are joined by mutual contact without any separation. Among the hens there are those laying all twin eggs, in which has been found what I said about the yolk. A hen had laid eighteen twin eggs, and hatched them, except those which (as it happens) were germ-free. From the other eggs hatched a chick, but the hence hatched twins are of that sort that one is larger, the other smaller: and finally the smaller one, last hatched, degenerates into freak, Aristotle. Some hens lay all twin eggs, and sometimes they hatch out twins, as Cornelius Celsus tells: one of the two chicks is larger, on the other hand they are claiming that twins are no hatching out at all, Pliny. Edward Wotton says: Also an ancient translator of Aristotle translates with the same meaning from Arabic as follows: And in whatever egg twins are found, one of the twins is small, the other is large: and often the small one is freakish.