‎"JOACHIMSTHAL, FERDINAND. - PRESENTATION COPY.‎
‎De Duabus Aequationibus quarti et sexti Gradus quae in Theoria linearum et superficierum Secundi Ordinis occurrunt. Commentatio Algebraica... Universitatum Litterarum Vratislaviensi..‎

‎Berlin, Typis Reimerianis, 1856. 4to.No wrappers as issued. (2),24 pp. Some additions in pencil on the first 3 pages. Inscribed on titlepage ""Viro amicissimo Kummer/ autore"" (Ernst Eduard Kummer, the famous mathematician, was Joachimsthal's teacher).‎

Reference : 45811

‎First edition of Joachimsthal's second ""Habilitationsschrift"" published the year when he was called to Breslau as professor in mathematics.Today Joachimsthal's name is associated with ""Joachimsthal Surfaces"", which possess a family of plane lines of curvature within the planes of a pencil" the Joachimsthal theorem concerning the intersection of two surfaces in three-dimensional real Euclidean space along a common line of curvature and a theorem on the four normals to an ellipse from a point inside it.‎