Projections stéréographiques (vues obliques). Méthode Francaise, elémentaire, de dessin linéaire basée sur le relief et sur l’unité de volume. 1ére (and) 2ième série. by Chrétien, L. V - no date (ca 1880): A complete set of geometric solids as teaching aid for drawing lessons

2 series in two wooden boxes (= all published). Each box contains 10 smaller wooden boxes (ca 110 x 110 x 100 mm), continuously numbered 1 through 20 each with different and variant numbers of geometric solids such as pyramid, prism, cylinder, cube, cone, and sphere made of cardboard, some of them hinged. Each box with with printed label with repeated main title, name of author and manuscript description of content pasted onto inside of hinged top lid of box (apart from two boxes in the première série).

Housed in two hand-crafted wooden boxes, sides covered with black paper, hinged top lid, interior lined with glazed green paper. Two metal clasps to each box and one metal handle. Oblong folio (590 x 260 x 130 mm). One clasp missing, extremeties worn, sides rubbed.

Cf. Heilmann/Nanobashvili/Pfisterer/Teutenberg. Lernt Zeichnen ! Techniken zwischen Kunst und Wiissenschaft 1525-1925 ; cf. Wolfgang Kemp. Zeichnen und Zeichenunterricht der Laien 1500-1870, pp. 300 ff (tendencies in 19th-century drawing lesson). A spectacular set of geometric solids constructed by Chrétien as a teaching aid in drawing classes to train spatial imagination by drawing a solid body on a flat surface. All the cardboard models of geometric solids presented here, except for the cylinder, cone and sphere models, are polyhedron variants that are arranged additively in 20 cubes in such a way that they accomodate exactly to the fill volume of the cube. The earliest work on such models seems to have been done in France, where the géométrie descriptive, founded by Gaspard Monge, offered the machine and construction technician welcome aids for the representation of the surfaces that mainly interested him. The collection of the Conservatoire des arts et metiers in Paris contains a number of models, some of them excellently executed, which were made in threads around 1830 on the basis of a hyperboloid constructed by Monge in 1814 at the suggestion of Prof. Olivier (at the École Polytechnique in Paris). Louis Benjamin Francoeur (1773-1849), a French mathematician and astronomer, a pupil of Gaspard Monge at the École Centrale des Travaux Publics who published some important textbooks was born into a famous Paris family of musicians. It was for his work on line drawing that Francoeur became most famous, the method he proposed being known as "Francoeur's method" which was published in 1819 in "Le dessin linéaire d'après la méthode de l'enseignement mutuel". All geometric solids excellently preserved with manuscript numbering and varying numbers of red dots on sides to assemble them in their respective sometimes quite complicate grouping to form a cube. The second box with manuscript entry on inside of lid "Diplôme d'honneur à l'éxposition de Châteauroux en 1882". It seems that this teaching aid for drawing classes was not produced in any significant numbers, judging by the manuscript annotations on the labels and other manuscript designs that might indicate a not yet fully commercialised version, but more likely to a privately issued project in a pre-publishing state. I could not trace a copy in institutional holdings. A scarce survivor.