Multiplication nomogram
The founders of the nomography
with intersection lines, 1797
Ézéchiel Pouchet (1748-1809)
Follow the straight horizontal and
vertical lines corresponding to two
given numbers: the product of these
numbers is provided by the side of
hyperbole intersected by the two lines.
Cotton Manufacturer of Rouen, Pouchet
has designed the Graphic tables for
unit conversions, necessary due to the
adoption of a new system of weights
and measures during the French
Revolution.
Multiplication nomogram
The founders of the nomography
with straight lines and algebraic
graduations, 1840
Léon Lalanne (1811-1892)
Follow the vertical and oblique lines
corresponding to two given numbers:
the product of these numbers is
provided by the side of the horizontal
line on which the two lines intersect.
Engineer of French Ponts et Chaussées
(Bridges and Roads Office), Lalanne
has simplified the Pouchet's abacus
introducing logarithmic scales on the
axes. Through this the hyperbole
become straight.
Multiplication nomogram
The founders of the nomography
hexagonal, 1885
Charles Lallemand (1857-1938)
Follow the oblique lines corresponding
to a green number and blue number:
the product of these numbers is
provided by the side of the horizontal
line on which the two lines intersect.
Lallemand imagined hex charts, using
three straight beam forming angles of
60°. The projection of a vector onto one
of the axes is the sum of the projections
on the other two axes, which allows a
graphic sum.
Multiplication nomogram
The founders of the nomography
with three intersecting lines, 1899 Maurice d’Ocagne (1862-1938)
Joining a number on the green scale
and a number of the blue scale by a
straight line, the intersection with the
red scale gives their product.
Maurice d'Ocagne uses the principle of
duality of projective geometry to
transform graphs with intersecting lines
in nomograms. All his life he worked
for the diffusion of nomography.
Multiplication nomogram with three lines, d'Ocagne 1899
Linking a green and a blue number by a straight line, the intersection with the red scale gives their product. This nomogram
is a modern incarnation of Menelaus theorem.
Multiplication nomogram
The founders of the nomography
circular, 1905
John Clark (?-?)
We know almost nothing about John Clark, except that he
Linking a green and a blue number in
was a professor at the Polytechnic of Cairo around 1905.
the circle with a straight line, the
intersection with the red diameter gives He designed many nomograms.
their product. The construction is done
with stereographic projection.
Multiplication nomogram with a scale with three gradations, Clark 1905
Linking a green and a blue number by a straight line the intersection with the red scale gives their product. The specificity of this nomogram
is that the three graduations are carried by the same curve, a system explored by Descartes and Roberval in the 17th century.
Multiplication nomogram
The founders of the nomography
with straight and hyperbolic lines, 2012 Alain Busser
Linking a green and a blue number of
the hyperbola with a straight line, the
intersection with the red axis gives their
product.
High school teacher at Roland Garros,
Reunion, France. It wants to illustrate
that nomography still offers a
challenging field of research.