Whether we look on Arnolfo as the son of Jacopo Tedesco, or only as the pupil of Niccolò Pisano, he was, either way, one of the guild; and more, a follower of Jacopo rather than of Niccolò, his bent being rather architectural than sculptural. We can, then, place Arnolfo as the first head of the _laborerium_ of Florence; and in tracing the formation of this branch of the guild, we shall throw a light on all the former branches, which, from want of systematic documents, have remained as formless organizations of _schola_, _laborerium_, and _Opera_. After trying in vain to find something more explicit about these organizations at the National Library and State Archives, I consulted the director of the Opera del Duomo, who kindly saved me the work of long puzzling over old MSS., by lending me a copy of Cesare Guasti's valuable collection of abstracts from the books of the _Opera_, from the earliest days of Arnolfo to the completion of the cathedral. Here the whole organization stands revealed. Here are the meetings of the lodge, and the subjects discussed; the names of the _Magistri_ and Council of Administration from year to year; the payments to architects, artists, and men; the legal contracts and business reports. It is clearly seen how the _Opera_ is connected with the _laborerium_, and how the meetings are always composed of some civic members from the Council of Administration, and some from the working Masters of the lodge. One, dated October 15, 1436, reports a meeting in the Opera del Duomo, at which the attendant _Operai_ or councillors were Ugo Alessandri, Donato Velluti, Nicolo Caroli de Macignis, and Benedict _Cicciaporci_ (pig's flesh); here's a nickname! They deliberated on the advisability of sending for a certain Francesco Livii de Gambasso, _Comitatus Florentiæ_, who was at Lubeck in Germany, to make the painted windows and mosaics. Francesco, when he came back to the city which he had known in his boyhood, and where he had learnt his art, bound himself to work in the _laborerium_ of the _Opera_, "et in dicta civitate Florentiæ in Laboreriis dictæ Operæ toto tempore suæ vitæ eidem continuum, ac firmum inviamentum exhiberent, ita, et taliter, quod ipse una cum sua familia victum, et vestitum in præfata Civitate erogare posset."[244] This one document gives valuable proof on several points. It proves that whether or not Italy got her architects from Germany, Italian Masters were employed in Germany. It proves that there was a guild in Florence, "Comitatus Florentiæ," to which Francesco Livii belonged, and that there was a _laborerium_ in Florence, in which Francesco, when a boy, had learned his art, and risen to the rank of Master. It proves, moreover, that the _laborerium_ was connected with the _Opera_. Another meeting of the same _Opera_ on November 26, 1435, held to consider all the designs for the choir of the Duomo, marks this connection still more plainly.