Between 1748 and 1773, the Venetian nobleman Pietro Gradenigo wrote his famous Notatori: 38 manuscripts today held in the Museo Correr Library in Venice -where he recorded the most important events in Venice and the neighboring territories. The notes are in chronological order. The Notatori resemble a diary containing over 22,000 reports concerning different disciplineshistory, economics, politics, art, -and news. At times, facts of daily life were the pretext for deepening the history and culture of Veneto. Pietro Gradenigo spent most of his life searching for documents about Venice. He frequented libraries and archives and transcribed many papers in his manuscripts with the help of his collaborators. His intention was to protect the historical memory and enhance the glorious past of Venice. For this reason, Gradenigo invited friends and colleagues to attend his library and consult what was contained in his precious manuscripts.

Recently the Notatori have been examined by scholars of specific disciplinary fields (for e.g. music and applied arts), in support of their research [1,2,3,4,5], but the only study entirely dedicated to them is Notizie d'arte tratte dai Notatori e dagli Annali del N.H. Pietro Gradenigo [6], edited by Lina Livan in 1942, that contains the transcription of some art notes. Given the importance of this source, the Notatori were the subject of a doctoral thesis of History, criticism and conservation of cultural heritage at the University of Padua [7], where the figure of Pietro Gradenigo and his working method were examined. Especially the notes of historical-artistic subject have been analyzed, first dividing them by a topic, for e.g., architecture, painting, sculpture, goldsmith, archaeology, graphic, and so forth, then, associating to each ones a group of keywords.

In order to make this collection available to researchers and preserve it, a relational database has been developed. This includes the transcriptions of each note's original texts and an additional corpus of associated metadata. In the Figure 1 the Entity-Relationship model used to represent the structure. To populate and to retrieve the information contained in the database we created the so-called Portale Gradenigo: a dedicated web portal which relies on finding and inserting content. This web portal has been designed to be easy to learn and fast to use, including a simple system of word-matching search engine.

In addition to the topic, each note is associated with one or more keywords, where elements like persons, places and items are reported. This is particularly useful when foreign names in the text are reported in an Italian version or there are terms in Venetian dialect. The purpose of keywords is to make the text even more accessible. Assigning a topic or keyword also makes a note understandable or provides further information. For example, in some notes, Gradenigo did not express the name of the author of a painting or an engraving but, if this is known, it can be added like keyword. Often, in addition to the notes, Gradenigo put references to other notes of a similar subject from the Notatori or other manuscripts of his where to deepen the topic. In the Portale were also inserted these references plus others proposed by us on the basis of an analysis of the entire manuscript production of Gradenigo. For example, Gradenigo recorded that Venice donated a medal to the ambassador Caracciolo in 1749 in the Notatori and in other manuscripts, so in the Portal have been added references to all the manuscripts of Gradenigo where this news is present. Pietro also described a print that Giambattista Piazzetta engraved to celebrate this event. This information has also been included in the Portal with a link to the online catalogue of the Fondazione Musei Civici di Venezia (MUVE) where a copy of this engraving is kept.

Using the topic and the keyword metadata it is also possible to show only the notes associated to specific categories. Being the text transcription make using HTML tags, it is possible in this way preserve specific annotations presented in the original text and show them in the browser. This tool permits to researches to filter the notes of interest, that would otherwise be difficult to locate. To assign a topic or a keyword also allows to make a note understandable or to have further information, for example in some cases Gradenigo did not express the name of the author of a painting or an engraving. Again Portale Gradenigo give us the possibility to analyzing the connections and the working practice of Pietro Gradenigo: a note may be important for the information it contains or to identify the interests of the author.

In the next steps we would like to include into the Portale all the 22,000 news contained in the Notatori and to add the topics hitherto excluded, like economy, politics, music, numismatics, and so forth. We hope that the Portale will become an instrument to obtain the complete digitisation of the collection. To accomplish this aim we would like to use it to index all the manuscripts of Pietro Gradenigo: around 300 titles [8], 230 of them are preserved in Museo Correr Library. Some manuscripts contain notes like in the Notatori, others are chronicles, genealogies, reports, etc., but the Portale can adapt to different needs. Another application is the design of an automatic topic classification. It aims to develop a system which automatically recognizes the newest notes added to the database. Actually the archive contains about 3,500 notes, each manually classified, so the ten percent of the total of the estimated numbers of notes. Being the different reports of interest for a large spectrum of researchers (e.g., historians of art, economist, historian, etc.) it could be important to subdivided the records immediately when the text is recorded. For this reason we are developing a Naive Bayes text classification system, which aims to assist during the transcription process, providing the probability of the new text associated to each topics. In this way the project could become a modern tool to continue in the action of preservation and enhancement of the Venetian cultural heritage, initiated by Gradenigo.