Wikipedia (20130604) "Una .... Esta máquina fue ideada por el militar, arquitecto e inventor
alemán Johann Helfrich von
Müller[1]
y redescubierta por el matemático británico Charles
Babbage, ninguno de los cuales llegó a construirla." 1 «Biography of Thomas Müller». http://es.wikipedia.org/wiki/M%C3%A1quina_diferencial Difference engine Wikipedia (20130604) A difference engine is an
automatic mechanical calculator designed to tabulate polynomial
functions. The name derives from the method of divided differences, a way to interpolate or
tabulate functions by using a small set of polynomial coefficients. Both logarithmic
and trigonometric functions, functions
commonly used by both navigators and scientists, can be approximated
by polynomials, so a difference engine can compute many useful sets of
numbers. The historical difficulty in
producing error free tables by teams of mathematicians and human
"computers" spurred Charles
Babbage's desire to build a mechanism to automate the process. …. J.
H. Müller, an engineer in the Hessian army, conceived of the idea of a
difference machine. This was described in a book published in 1786, but
Müller was unable to obtain funding to progress with the idea http://en.wikipedia.org/wiki/Difference_engine "The German engineer and master
builder—Johann Helfrich Müller (1746-1830) (see biography of Johann Müller) is a very interesting figure in the world of mechanic calculators,
not only for his small calculator, an improved version of the machine of Philipp Hahn, which he created, but for his plans to build a difference engine
almost 40 years before Charles Babbage. He also wanted to built a machine,
that was capable of being configured to use Leibnitz's arithmetica dyadica. ….. …. in a
book published in Frankfurt and Mainz in 1786. This 50 page booklet was
edited by Müller's friend Philipp Engel Klipstein… … under
the heading "Further inventions of superior calculating machines and an
arithmetical printing machine" …. In these passages, it is made clear
that Müller, perhaps at an even earlier date, had invented a difference
engine (to operate to the third order of difference) for the rapid production
of error-free tables, by means of "whole series of numbers" and by
using "difference-numbers" (Differenzzahlen). A description similar
to that in the postscript to Lichtenberg is given of the printing part, which
was supposed to print directly onto paper, rather than produce matrices for
stereotypes. No mention is made of how the necessary mechanisms to accomplish
this were to be designed. Nonetheless it is clear from this document that
Johann Müller had conceived the idea of a difference engine by the year 1786.
Such a machine will be proposed almost 40 years later by Charles Babbage (see
the differential engine of Babbage). It is known that several chapters of the
book have been translated for Charles Babbage by John Hershel. However, the
date of this translation is unknown and the question remains whether some of
Müller's ideas have been used for Babbage's machines" The calculating machines of Johann Helfrich Müller http://history-computer.com/MechanicalCalculators/18thCentury/Muller.html |