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


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 slide rule, pascaline and mechanical calculator, I organize international lectures and exhibitions where the ancient instruments could be tested by the public.

"Boring exhibits leave no trace"

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.

Download the short history of engineering before computers by Nicola Marras

Short history of engineering before computers

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.

Download the presentation of the communication exhibit by Nicola Marras

Presentation of the exhibition on communications (Italian)

Download the presentation of the pre-GPS navigation exhibit by Nicola Marras

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!

Download Was There Life Before Computer by Nicola Marras

The history of mechanical calculator and slide rule

Review of my history of calculation on Hackaday

Routledge slide rule

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

Pickett 600 ES slide rule on the Apollo 11

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.

Pascaline, a mechanical calculator

Pascalina mod Lightning, 1965

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 Calculator, 1975

Faber sliderule, 1975

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 electronic computer,1982

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.

Test if you notice any errors in this calculator

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.

@ Andy Singer

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.

Download Analog Mind&Democracy by Nicola Marras

Analog Mind & Democracy

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

Exhibits and Didactic Aids

Exhibit of old calculators

Nicola Marras teachs pascaline and arithmometers

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

Nicola Marras' Staff

Best staff = best show!

Download the paper calculators by Nicola Marras

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

Upcoming Exhibits

Exhibit The Magic of Light and Shadow

The first Magic Lanterns allowed screen projections as early as the late 1600s. The shows accustomed the audience to seeing things and people non-existent and were called "phantasmagoria".
Over time, knowledge was formed about the formation of the image in the retina and the technologies of construction of the projectors, forming the context in which modern cinema could be born in 1895.

Upcoming Lectures

Speech Metaverse

Speech Technium

The program is being finalized, but the extreme instability of the international situation makes it difficult to predict its viability.

Speech Marionettes

Essential Library

For those who want to approach the world of analogue calculations, there is nothing better than Collecting Slide Rules and All About Slide Rules, both free by the Oughtred Society.
At the International Slide Rule Museum we find a library, where numerous texts and instructions can be downloaded for free. An excellent slide rule seminar is also available at the ISRM.

Cover of Collecting Slide Rule     Cover of All About Slide Rules     Immagine ISRM Library

About Me and the Website

As obvious, I carry out my project in Italy and and this translation is much smaller than the original. However, here you will find a summary of my book on the history of the calculating instruments and all my educational material. My works are provided under the CC License "BY-NC-SA 3.0".

The contents were produced by myself, but there is also material owned by third parties or taken in the internet, apparently of public domain. In general I applied for authorization to use, which unfortunately is not always possible. In any case is always shown on the author's name and a link to his personal website: if the name of the owner is not present must be considered the author as unknown to me.
If someone noticed that, unbeknownst to me, there is copyrighted material is encouraged to communicate it to me, so I can properly cite the intellectual property or remove it. It is my intention to apply all the rules in force on the legal protection of intellectual property.

Nicola Marras foto and bio

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