The ancient plans allow us to understand the project zand to compare it with the execution, which is a useful exercise to preserve and repair the construction.
The construction started in 1767 and dragged until 1775, one year after the death of Louis XV. It was undertajken in two phases. The southern section of the building was built first and the large italian loungee, to the north, was added later (1774) with a belvedere terrace at its top to allow the king to wath the hunting party. That latter chice was inspired from a similar addition to the earlier castle of François Ier, by Philibert de l’Orme, at the top of the construction by Pierre Chambiges.
The outside appearance especially on the southern side is exemplary of the change of taste in the work of Gabriel following the publication of the « Ruins of the most beautiful monuments of Greece » (1758) par Julien-David Le Roy : sculpted ornaments, columns and pilasters disappear and are replaced by an utterly sober design in the « greek taste ». To the North, the construction incorporates curved or beveled shapes and alternately straight and curved openings, as in the earlier works of Gabriel such as pavillon du Butard and pavillon de France.
The astonishing plan of the additions planned by king Charles X, in the Catalogue of Hunts of Saint Germain, 1827. We can see here the second stalls, to the left, unfortunately destroyed in the 1970s, and additions to the house of the gamekzeeper, which were never completed.
Plan by Gabriel with the two construction phases of the pavilion :
– in black, first phase in the third quarter of the XVIIIth century encompassing the central hall, the western hall of the hunting officers, a staircase and a bathroom.
– in grey, second phase in the very last year of the reign of Louis XV/beginning of Louis XVI : the octogonal « italian » lounge and the terrasses. The drawing seemingly includes a railing which is not present today.
Plan of the first floor of the pavillon. It consisted of thwo rooms and a corridor, a service room, the ection to the nort being part of the two-floored octogonal lounge. At only 2.6 meters of height it is much more intimate than the 4.5 meters tall rooms of the ground floor. This plan was transformed under Napoleon to create a slightly smaller room un the central section.
Sectional view of the building by Gabriel showing the massive underground rooms, the southern hall, the first floor, the attic and, to the right, the large octagonal « italian » lounge.
Sixty years after the sectional view of Gabriel, this view in the Catalogue of the hunts of Saint Germain confirms that the decor of the italian hall was executed according to plan. It shows a decor for the southern entrance hall which is consistent with what appears today. Therefore, its illustration of the decor of the first floor, in what used to be the room of Napoleon (lost today) is probably accurate.
Plan of the caves. It includes the southern and western kitchens and a third one to the northwest, plus two cellars. The largest kitche oncludes a bread oven which still exists today along with a very large L shaped « table potagère » similar to those in the « réchauffon » of Petit Trianon. To the north, uner the terraces, there are still two smaller cellars whiche are remants from the Francois Ier castle.