His most important colleague in the faculty was the famous Montanus, professor of medicine.
Among his students and associates was the Englishman Caius, who lived in the same house with him.

When the output is considered, he cannot have had much spare time at Padua.
He did not create human anatomy--that had been done by the Alexandrians--but he studied it in so orderly and thorough a manner that for the first time in history it could be presented in a way that explained the entire structure of the human body.

Early in 1542 the MS.
was ready; the drawings had been made with infinite care, the blocks for the figures had been cut, and in September, he wrote to Oporinus urging that the greatest pains should be taken with the book, that the paper should be strong and of equal thickness, the workmen chosen for their skill, and that every detail of the pictures must be distinctly visible.
He writes with the confidence of a man who realized the significance of the work he had done.

It is difficult to speak in terms of moderation of the "Fabrica." To appreciate its relative value one must compare it with the other anatomical works of the period, and for this purpose I put before you two figures from a text-book on the subject that was available for students during the first half of the sixteenth century.
In the figures and text of the "Fabrica" we have anatomy as we know it; and let us be honest and say, too, largely as Galen knew it.

Time will not allow me to go into the question of the relations of these two great anatomists, but we must remember that at this period Galen ruled supreme, and was regarded in the schools as infallible.