Da Vinci, Leonardo

Cyber Hero of the past –

“Leonardo da Vinci was like a man who awoke too early in the darkness, while the others were all still asleep”  (Sigmund Freud)

This famous Renaissance painter, sculptor, engineer, architect, mathematician and inventor was born in Vinci (hence his “surname”) in Tuscany, Italy on April 15, 1452. Being the son of a wealthy Florentine, he received the best education that Florence, where his family has settled in the mid 1460s, could offer. About 1466 he started as an apprentice in the studio of Andrea del Verrochio, a leading painter and sculptor in his day. In 1478 Leonardo started on his own as a master painter.

In 1482 he settled in Milan where he painted the Last Supper (1498), a mural in the refectory of the local Monastery of Santa Maria delle Grazie. In 1502 he entered the services of Cesare Borgia in Florence as an architect and engineer, where he supervised the work on the fortresses of the papal territories. It is in Florence that he painted his most famous painting, the Mona Lisa (in the period 1503-1506, Louvre), also known as La Gioconda, after the presumed name of the women’s husband, Francesco del Giocondo. The lady’s enigmatic smile has intrigued its viewers ever since.

As a scientist he knew the importance of careful observation and precise documentation. Most of his scientific creations never made it further than the drawing board and even his scientific notations were not published in his time. His theories and inventions were written down on many loose pages, most of which were written in mirror script that could best be read by holding it up to a mirror. The reason for this way of writing is unknown.

Had his theories been published during his lifetime, they probably would have revolutionized the science of the 16th century as he anticipated many discoveries of modern times. His drawings cover an underwater diving suit, a helicopter, flying machines, water mills, draglines, escalators, weapons of war like an enormous crossbow and a catapult, and many other ingenious contraptions. The human anatomy also fascinated him and he dissected many corpses to study the underlying structure, muscles, heart, blood circulation system, skeleton, etc. This has resulted in his many detailed and surprisingly accurate anatomical sketches. One of his other well-known drawings is the famous Vitruvian Man which became part of the opening scene of Dan Brown’s recent bestseller The Da Vinci Code. This book has, like no other, interested many people in the works of Da Vinci, resulting in specially organized Da Vinci tours through the Louvre and through Rome.

In 1516 he entered the service of King Francis I who had conquered Milan, so Leonardo was invited by the king to travel to France where he spent his last years in Chateau de Cloux near Amboise where he died on May 2, 1519.

The many papers and notebooks with his scientific and artistic drawings and annotations were only collected after his death and in ca 1600 a massive 10 volumes of papers were collated to form the Codex Atlanticus (Ambrosiana library, Milan).

One of Leonardo’s lesser-known inventions is a mechanical adding machine which came to light with the rediscovery of two of his notebooks in 1967 which had been missing for 200 years.  The story of these manuscripts and the controversial replica of this calculator was discovered and documented by Erez Kaplan who noticed a picture of the Da Vinci Calculator in the book “The History of Computing” by Marguerite Zientara. For his full story, see  http://www.webcom.com/calc/leonardo/leonardo.html

Kaplan writes: “On February 13th 1967 an amazing discovery was made by American researchers working in the National Library of Spain, Madrid. They had stumbled upon 2 unknown works of Leonardo da Vinci know as the “Codex Madrid”. There was much excitement regarding this discovery and the public officials stated that the manuscripts “weren’t lost, but just misplaced”. The rediscovered notebooks contained a drawing by Leonardo with what looks like an early adding machine using geared wheels.

Kaplan then goes on to describe the building of a replica of this adding machine by Dr Roberto Guatelli, a Da Vinci expert who had specialized in building working replicas of Da Vinci machines. The replica was built in 1968 for IBM which had a travelling exhibition of their machines.

The Guatelli replica of the Da Vinci Calculator

The text beside the replica said:

Device for Calculation: An early version of today’s complicated calculator, Leonardo’s mechanism maintains a constant ratio of ten to one in each of its 13 digit-registering wheels. For each complete revolution of the first handle, the unit wheel is turned slightly to register a new digit ranging from zero to nine. Consistent with the ten to one ratio, the tenth revolution of the first handle causes the unit wheel to complete its first revolution and register zero, which in turn drives the decimal wheel from zero to one. Each additional wheel marking hundreds, thousands, etc., operates on the same ratio. Slight refinements were made on Leonardo’s original sketch to give the viewer a clearer picture of how each of the 13 wheels can be independently operated and yet maintain the ten to one ratio. Leonardo’s sketch shows weights to demonstrate the equability of the machine.”

Controversy arose later regarding this replica as some objectors claimed that the Da Vinci drawing did not represent an adding machine but a gear ratio machine and that Dr Guatelli had gone “beyond the statements of Leonardo.”

Following this controversy, IBM decided to withdraw the replica from its display and its currents whereabouts are unknown, probably somewhere in IBM’s archival storages.

© Wobbe Vegter, May 2005   see http://wvegter.hivemind.net