Download my history of the calculating instruments in pdf (English)

Intro

Modern world was designed with slide rule and mechanical calculator

Still the youth ignore these instruments that anticipated our technology. I think it's useless to teach math without teaching how calculations were made in the past.

With my free e-book "Nicola Marras: Was There Life Before Computer?" the teachers can easily illustrate the old computing systems.

To preserve the memory of the slide rule, the pascaline and the mechanical calculator, I organize international exhibitions and conferences, where the ancient instruments could be tested by the public.

Short history of engineering before computers

To better understand the old technology I had also added exhibits on the history of communications and pre-GPS navigation. All programs still available in Italian and English.
The exhibits were presented in London, Berlin, San Francisco, Slubice, Trento etc, as well from 2007 until 2018 at The Cagliari Festival Scienza.
The project is now suspended due to other commitments.

Presentation of the exhibition on communications (Italian)

Presentation of the exhibition on pre-GPS navigation (Italian)

Milestones in Analog & Digital Computing

The modern computer has been built on ancient instruments, conceived in the 17th century, that seemed irreplaceable.
Galileo's compass was still useful on board aircraft carriers, the mechanical calculator and the pascaline were the driving force of the financial globalization. The slide rule, invented in 1622, served to design everything: from the James Cook's flagship to the Jumbo Jet!

The history of mechanical calculator and slide rule

Review of my history of calculation on Hackaday

Earth, 1800: the inventor Joshua Routledge and his slide rule

Moon, 1969: the astronaut Buzz Aldrin and his slide rule

It was hard to fathom a world without them, but in 1972 the introduction of the first modern calculator caused slide rules and mechanical calculators to disappear instantly. It was Leibniz's dream come true:

"It is unworthy of excellent men to lose hours like
slaves in the labor of calculation which could be
relegated to anyone else if machines were used"

No invention ever made such a rapid impact. The automobile took more than twenty to establish itself. Electronics instead instantly defeated the competition. An unprecedented revolution.

Mechanical calculator: very similar the models of 1645 and 1965

However, the transition was not painless because the ancient computers were used in every field. People had little faith in the new "electronic slide rule" and the factories inserted the old instrument on the back, for the sake of safety.

Faber TR3 calculator with "safety" sliderule on the back, 1975

By now, however, the new technologies required computing power: shortly after Sharp presented the first mini computer, almost pocket-sized. The PC era was beginning.

Sharp PC 1500 programmable computer with printer, 1982

A little investigation revealed to me that, for many students, the result of 2 + 3 x 4 is 20, not 14! With the slide rule, however, the pupils immediately recognize the order of the operations. The pascaline helps the little ones to easily understand addition and carry-over.

Was there life before computer? educational project has
represented Italy at the Science on Stage Europe Festival 2013

Old Calculators & Democracy

Today people punch numbers into a calculator and expect the calculator to provide the correct answer, the Art of Numeracy is no longer practiced and the world before computers almost forgotten.
Now students learn mathematics while being illiterate about the history of mathematics, which is a false start. With a calculator, modified to give incorrect results, I show how easy one can make and no notice errors.

The operation that appears on the display is correct?
Check if you notice any errors in this calculator

The electronic aids should not blindly be trusted. We need to understand and criticize what we do. Software could be buggy and the computer results have to be critically reviewed. In the past, with the old calculating devices, the operators were always aware of their actions and used to check the results.
Today instead many people think "I don't need to check, the computer knows better than me". Sadly, the thinking that "if an expert states it, then it must be true" is the basis of the Authority Principle, which leads to mental slavery.

We'll believe anythings (if it lets us be lazy ...) @ Andy Singer

Teaching the traditional calculating instruments as a school of democracy may seem an overstatement, but nobody can be a free citizen if unaware of what he does or willing to discuss it.
Not by chance democracy was born in the same country in which maths and geometry were born: uncritical use of the computer can lead people to press buttons mindlessly.

Scientific thinking and independence of ideas are not a natural product of intelligence, they must be cultivated steadily. A simple lesson about traditional calculation may help. A rational mind produces better decisions, better citizens and a better world.

Old Calculators & Democracy

"Old Calculators & Democracy" educational project has
represented Italy at the Science on Stage Europe Festival 2015

Exhibits and Didactic Aids

Even the little ones take an active interest:
pascalines and slide rule are not yet forgotten

Best staff = best show!

Download the templates of: E6B, slide rule, nomograms, abaques