According to Jan Paszenda, the brief description of the design showing plan of extension of the church, mentioned in the auction catalogue of drawings by Giacomo Briano (actually in the Getty Research Institute collections in Los Angeles), refer to the rebuilding and extension of the St John church in Jaroslaw (1616-1624). The author gices a detailed analysis of the drawings in question.The plan and a view of a three-storeyed tower with alternative solution of the roof (on the verso of the sheet XXIX) was supposed (John Bury) to be a design either for the monastic country villa of S. Martino in Forli (which he based on the fact that beside its view Briano had written the word 'dovecote') or for St John's Church in Jaroslaw. A comparison with the drawing depicting the S. Martino villa, in which the towers are set on the axes of the layout, in the enclosure of the building, permits the rejection of the first hypothesis; it rules out the second supposition as well. However, the discussed plan closely resembles the plan of the tower drawn in a design for the Jesuit college in Lublin, which has been preserved in the collections of the Lvov University Library. The second drawing on the verso of sheet no. XXIX, on the right-hand side, represents the plan of an unidentified church and monastic buildings (a college?). It seems that the closest affinities with the structure shown in the drawing should be sought in the architecture of Observantine churches. Another Briano's drawing (no. XL) which John Bury has hitherto erroneously considered to belong to one set together with the drawings on sheets XIII and XIV (presenting a design for a Jesuit college at Ostróg (?) and the façade of the Church of SS. Peter and Paul in Cracow), should actually be linked with the remodelling of St John's Church in Jaroslaw.The drawings determine the dating of the history of extension of the edifice. The original church was immediately provided with side chapels and part of the porch. The chapels were domed, as they are today. The parapet on the southern chapel was designed by Briano. Thus the entire remodelling work on the church was carried out before the 1625 fire, during Briano's first stay in the Polish Commonwealth (1616-1621) as it was then that he performed the function of inspector of the Jesuit 'fabricae'.
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