Heider, Eduard J. Theory of lean vaults and their practical execution. VIII, 91 p. With 2 copper tablets by Wernigk. 21,5 x 13,5 cm. Marbled half leather d. Zt. with red back shield and some back gilding (minimum rubbing). Vienna, C. Gerold, 1846. Engelmann Suppl. 47. Niner S. 402 and 1333. – First edition. "The purpose of the present writing is to prove that a crooked vault can be produced not only with the same ease as a vertical one, but also for any position and shape of the backs, for each surface and building material without exception, according to the laws of stability. (Preface) J. Heider (1818-1876) was a civil servant at the General Directorate of the Austrian State Railways, later Technical Director of the Arsenals Buildings of Lloyd in Trieste, Austria. Provenance: Title with stamp of the building department of the Hanoverian Oberhofmarschallsamt "O.H.M.A. / Bau Departement".