My question is based on the information given in the book "the tangled origins of the leibnizian calculus", at pages 108 -109. I know that leibniz invented the stepped drum and used it to build the stepped reckoner - that first mechanical calculator capable of doing all four arithmetical operations. He also sketched a design for a different machine - the pinwheel calculator, designed a cipher machine, developed the binary arithmetic (based on 0 and 1) and established it's importance for computers, and even described in detail some of the fundamental principles of the modern computer (in his treatise "De progressione Dyadica"). With such achievements in hand, it's not an exageration to believe the statement in this book. So my question is, like many other questions of mine, can someone give a reference for leibniz's supposed machine? can someone give a reference for a drawing of leibniz machine (how does it look like?).
I've found an indirect reference into:
- Joseph Ehrenfried Hofmann, Leibniz in Paris 1672-1676 (1974, German ed.1949), page 30 and footnote 27:
still in 1674 he [Leibniz] has plans for constructing an "analytical" counterpart to his calculating machine, an instrument for determining the solutions of equations, and he actually succeeds in doing so [footnote 27]
Footnote 27 for details see Hofmann (1970) ["Uber fruhe mathematische Studien von G.W.Leibniz", Studia Leibnitiana, 2, 81-114] : 101-4. The instrument is mentioned in letters to Oldenburg: June, July, Dec.1675; also in L-Huygens, mid-Sept.1675. From Huygens' rather cautious reply, 30 Sept.1675 we may conclude that he has seen a sketch of the "Compas d'equation", as had Tschirnhaus according to Leibniz's letter, 8 Jan.1694. [...] A similar instrument is described in the Encyclopédie, Suppl.II (1776): 834-5 (with an illustration in the Planche suppl.(1777)) under "Algèbre". This instrument works for quadratic equations only, but it is justly claimed as a prototype capable of adaptation to higher equations. The inventor is not named: he might indeed have been inspired by the hint in G.W.Leibniz, Der Briefwechsel mit Mathematikern I (Berlin 1899): 146 since the passage was available in print, in John Wallis, Opera mathematica III (Oxford 1699): 620-2 where the letter in question is reproduced, and in Commercium Epistolicum (1712): 45 where an excerpt is given [...].