Science and inventions of Leonardo da Vinci

Leonardo da Vinci (1452–1519) was an Italian polymath, regarded as the epitome of the "Renaissance Man", displaying skills in numerous diverse areas of study. Whilst most famous for his paintings such as the ''Mona Lisa'' and the ''Last Supper'', Leonardo is also renowned in the fields of civil engineering, chemistry, geology, geometry, hydrodynamics, mathematics, mechanical engineering, optics, physics, pyrotechnics, and zoology.

While the full extent of his scientific studies has only become recognized in the last 150 years, during his lifetime he was employed for his engineering and skill of invention. Many of his designs, such as the movable dikes to protect Venice from invasion, proved too costly or impractical. Some of his smaller inventions entered the world of manufacturing unheralded. As an engineer, Leonardo conceived ideas vastly ahead of his own time, conceptually inventing the parachute, the helicopter, an armored fighting vehicle, the use of concentrated solar power, a ratio machine that could be used in an adding machine, a rudimentary theory of plate tectonics and the double hull. In practice, he greatly advanced the state of knowledge in the fields of anatomy, astronomy, civil engineering, optics, and the study of water (hydrodynamics).

One of Leonardo's drawings, the ''Vitruvian Man'', is a study of the proportions of the human body, linking art and science in a single work that has come to represent the concept of macrocosm and microcosm in Renaissance humanism.

Approach to scientific investigation

During the Renaissance, the study of art and science was not perceived as mutually exclusive; on the contrary, the one was seen as informing upon the other. Although Leonardo's training was primarily as an artist, it was largely through his scientific approach to the art of painting, and his development of a style that coupled his scientific knowledge with his unique ability to render what he saw that created the outstanding masterpieces of art for which he is famous.

As a scientist, Leonardo had no formal education in Latin and mathematics and did not attend a university. Because of these factors, his scientific studies were largely ignored by other scholars. Leonardo's approach to science was one of intense observation and detailed recording, his tools of investigation being almost exclusively his eyes. His journals give insight into his investigative processes.

As a researcher, Leonardo divided nature and phenomena into ever smaller segments, concretely with knives and measuring instruments, intellectually with formulas and numbers, to wrest the secrets of creation from it. The smaller the particles, runs the assumption; the closer one will get to the solution of the enigmas.

A recent and exhaustive analysis of Leonardo as a scientist by Fritjof Capra argues that Leonardo was a fundamentally different kind of scientist from Galileo, Newton, and other scientists who followed him, his theorizing and hypothesizing integrating the arts and particularly painting. Capra sees Leonardo's unique integrated, holistic views of science as making him a forerunner of modern systems theory and complexity schools of thought.

Leonardo's notes and journals

Leonardo kept a series of journals in which he wrote almost daily, as well as separate notes and sheets of observations, comments and plans. He wrote and drew with his left hand, and most of his writing is in mirror script, which makes it difficult to read. Much has survived to illustrate Leonardo's studies, discoveries and inventions.

On his death, the writings were left mainly to his pupil and heir Francesco Melzi, with the apparent intention that his scientific work should be published. Sometime before 1542, Melzi gathered together the papers for ''A Treatise on Painting'' from eighteen of Leonardo's 'books' (two-thirds of which have gone missing). The publishing did not take place in Melzi's lifetime, and the writings were eventually bound in different forms and dispersed. Some of his works were published as ''A Treatise on Painting'' 165 years after his death.

Publication

Leonardo illustrated a book on mathematical proportion in art written by his friend Luca Pacioli and called '' De divina proportione'', published in 1509. He was also preparing a major treatise on his scientific observations and mechanical inventions. It was to be divided into a number of sections or "Books", Leonardo leaving some instructions as to how they were to be ordered. Many sections of it appear in his notebooks.

These pages deal with scientific subjects generally but also specifically as they touch upon the creation of artworks. In relating to art, this is not science that is dependent upon experimentation or the testing of theories. It deals with detailed observation, particularly the observation of the natural world, and includes a great deal about the visual effects of light on different natural substances such as foliage.''Jean Paul Richter'' editor 1880,
The Notebooks of Leonardo da Vinci
' Dover, 1970, . (accessed 2007-02-04)

Leonardo wrote:

Begun at Florence, in the house of Piero di Braccio Martelli, on the 22nd day of March 1508. And this is to be a collection without order, taken from many papers which I have copied here, hoping to arrange them later each in its place, according to the subjects of which they may treat. But I believe that before I am at the end of this askI shall have to repeat the same things several times; for which, O reader! do not blame me, for the subjects are many and memory cannot retain them lland say: 'I will not write this because I wrote it before.' And if I wished to avoid falling into this fault, it would be necessary in every case when I wanted to copy passagethat, not to repeat myself, I should read over all that had gone before; and all the more since the intervals are long between one time of writing and the next.

Natural science

Light

Leonardo wrote:

The lights which may illuminate opaque bodies are of 4 kinds. These are; diffused light as that of the atmosphere; And Direct, as that of the sun; The third is Reflected light; and there is a 4th which is that which passes through ranslucentbodies, as linen or paper etc.

For an artist working in the 15th century, some study of the nature of light was essential. It was by the effective painting of light falling on a surface that ''modelling'', or a three-dimensional appearance was to be achieved in a two-dimensional medium. It was also well understood by artists like Leonardo's teacher, Verrocchio, that an appearance of space and distance could be achieved in a background landscape by painting in tones that were less in contrast and colors that were less bright than in the foreground of the painting. The effects of light on solids were achieved by trial and error, since few artists except Piero della Francesca actually had accurate scientific knowledge of the subject.

At the time when Leonardo commenced painting, it was unusual for figures to be painted with extreme contrast of light and shade. Faces, in particular, were shadowed in a manner that was bland and maintained all the features and contours clearly visible. Leonardo broke with this.
In the painting generally titled ''The Lady with an Ermine'' (about 1483) he sets the figure diagonally to the picture space and turns her head so that her face is almost parallel to her nearer shoulder. The back of her head and the further shoulder are deeply shadowed. Around the ovoid solid of her head and across her breast and hand the light is diffused in such a way that the distance and position of the light in relation to the figure can be calculated.

Leonardo's treatment of light in paintings such as '' The Virgin of the Rocks'' and the ''Mona Lisa'' was to change forever the way in which artists perceived light and used it in their paintings. Of all Leonardo's scientific legacies, this is probably the one that had the most immediate and noticeable effect.

Human anatomy

Leonardo wrote:

...to obtain a true and perfect knowledge ... I have dissected more than ten human bodies, destroying all the other members, and removing the very minutest particles of the flesh by which these veins are surrounded, ... and as one single body would not last so long, since it was necessary to proceed with several bodies by degrees, until I came to an end and had a complete knowledge; this I repeated twice, to learn the differences...

Topographic anatomy

Leonardo began the formal study of the topographical anatomy of the human body when apprenticed to Andrea del Verrocchio. As a student he would have been taught to draw the human body from life, to memorize the muscles, tendons and visible subcutaneous structure and to familiarise himself with the mechanics of the various parts of the skeletal and muscular structure. It was common workshop practice to have plaster casts of parts of the human anatomy available for students to study and draw.

If, as is thought to be the case, Leonardo painted the torso and arms of Christ in '' The Baptism of Christ'' on which he famously collaborated with his master Verrocchio, then his understanding of topographical anatomy had surpassed that of his master at an early age as can be seen by a comparison of the arms of Christ with those of John the Baptist in the same painting.

In the 1490s he wrote about demonstrating muscles and sinews to students:

Remember that to be certain of the point of origin of any muscle, you must pull the sinew from which the muscle springs in such a way as to see that muscle move, and where it is attached to the ligaments of the bones.

His continued investigations in this field occupied many pages of notes, each dealing systematically with a particular aspect of anatomy. It appears that the notes were intended for publication, a task entrusted on his death to his pupil Melzi.

In conjunction with studies of aspects of the body are drawings of faces displaying different emotions and many drawings of people suffering facial deformity, either congenital or through illness. Some of these drawings, generally referred to as "caricatures", on analysis of the skeletal proportions, appear to be based on anatomical studies.

Dissection

As Leonardo became successful as an artist, he was given permission to dissect human corpses at the Hospital of Santa Maria Nuova in Florence. Later he dissected in Milan at the hospital Maggiore, and in Rome at the Ospedale di Santo Spirito (the first mainland Italian hospital). From 1510 to 1511 he collaborated in his studies with the doctor Marcantonio della Torre.

I have removed the skin from a man who was so shrunk by illness that the muscles were worn down and remained in a state like thin membrane, in such a way that the sinews instead of merging in muscles ended in wide membrane; and where the bones were covered by the skin they had very little over their natural size.

In 30 years, Leonardo dissected 30 male and female corpses of different ages. Together with Marcantonio, he prepared to publish a theoretical work on anatomy and made more than 200 drawings. However, his book was published only in 1680 (161 years after his death) under the heading ''A Treatise on Painting''.

Among the detailed images that Leonardo drew are many studies of the human skeleton. He was the first to describe the double S form of the backbone. He also studied the inclination of pelvis and sacrum and stressed that sacrum was not uniform, but composed of five fused vertebrae. He also studied the anatomy of the human foot and its connection to the leg, and from these studies, he was able to further his studies in biomechanics.

Leonardo was a physiologist as well as an anatomist, studying the function of the human body as well as examining and recording its structure. He dissected and drew the human skull and cross-sections of the brain, transversal, sagittal, and frontal. These drawings may be linked to a search for the ''sensus communis'', the locus of the human senses, which, by Medieval tradition, was located at the exact physical center of the skull.

Leonardo studied internal organs, being the first to draw the human appendix and the lungs, mesentery, urinary tract, reproductive organs, the muscles of the cervix and a detailed cross-section of coitus. He was one of the first to draw a scientific representation of the fetus in the intrautero.

Leonardo studied the vascular system and drew a dissected heart in detail. He correctly worked out how heart valves ebb the flow of blood yet he did not fully understand circulation, as he believed that blood was pumped to the muscles where it was consumed. In 2005 a UK heart surgeon, Francis Wells, from Papworth Hospital Cambridge, pioneered repair to damaged hearts, using Leonardo's depiction of the opening phase of the mitral valve to operate without changing its diameter allowing an individual to recover more quickly. Wells said "Leonardo had a depth of appreciation of the anatomy and physiology of the body – its structure and function – that perhaps has been overlooked by some."

Leonardo's observational acumen, drawing skill, and the clarity of depiction of bone structures reveal him at his finest as an anatomist. However, his depiction of the internal soft tissues of the body are incorrect in many ways, showing that he maintained concepts of anatomy and functioning that were in some cases millennia old, and that his investigations were probably hampered by the lack of preservation techniques available at the time. Leonardo's detailed drawing of the internal organs of a woman (See left) reveal many traditional misconceptions.Martin Kemp, ''Leonardo'', Oxford University Press, (2004)

Leonardo's study of human anatomy led also to the design of an automaton which has come to be called Leonardo's robot, was probably made around the year 1495 but was rediscovered only in the 1950s.

Comparative anatomy

Leonardo not only studied human anatomy, but the anatomy of many other animals as well. He dissected cows, birds, monkeys and frogs, comparing in his drawings their anatomical structure with that of humans. On one page of his journal Leonardo drew five profile studies of a horse with its teeth bared in anger and, for comparison, a snarling lion and a snarling man.

I have found that in the composition of the human body as compared with the bodies of animals, the organs of sense are duller and coarser... I have seen in the Lion tribe that the sense of smell is connected with part of the substance of the brain which comes down the nostrils, which form a spacious receptacle for the sense of smell, which enters by a great number of cartilaginous vesicles with several passages leading up to where the brain, as before said, comes down.

In the early 1490s Leonardo was commissioned to create a monument in honour of Francesco Sforza. In his notebooks are a series of plans for an equestrian monument. There are also a large number of related anatomical studies of horses. They include several diagrams of a standing horse with the angles and proportions annotated, anatomical studies of horses' heads, a dozen detailed drawings of hooves and numerous studies and sketches of horses rearing.

He studied the topographical anatomy of a bear in detail, making many drawings of its paws. There is also a drawing of the muscles and tendons of the bear's hind feet.
Other drawings of particular interest include the uterus of a pregnant cow, the hindquarters of a decrepit mule and studies of the musculature of a little dog.

Botany

The science of botany was long established by Leonardo's time, a treatise on the subject having been written as early as 300 BCE. Leonardo's study of plants, resulting in many picturesque drawings in his notebooks, was not to record in diagrammatic form the parts of the plant, but rather, as an artist and observer to record the precise appearance of plants, the manner of growth and the way that individual plants and flowers of a single variety differed from one another.

One such study shows a page with several species of flower of which ten drawings are of wild violets. Along with a drawing of the growing plant and a detail of a leaf, Leonardo has repeatedly drawn single flowers from different angles, with their heads set differently on the stem.

Apart from flowers the notebooks contain many drawings of crop plants including several types of grain and a variety of berries including a detailed study of bramble. There are also water plants such as irises and sedge. His notebooks also direct the artist to observe how light reflects from foliage at different distances and under different atmospheric conditions.

A number of the drawings have their equivalents in Leonardo's paintings. An elegant study of a stem of lilies may have been for one of Leonardo's early Annunciation paintings, carried in the hand of the Archangel Gabriel. In both the Annunciation pictures the grass is dotted with blossoming plants.

The plants which appear in both the versions of '' The Virgin of the Rocks'' reflects the results of Leonardo's studies in a meticulous realism that makes each plant readily identifiable to the botanist.

In ''A Treatise on Painting'', Leonardo proposed the following branching rule:

All the branches of a tree at every stage of its height when put together are equal in thickness to the trunk elow them

Geology

As an adult, Leonardo had only two childhood memories, one of which was the finding of a cave in the Apennines. Although fearing that he might be attacked by a wild beast, he ventured in driven "by the burning desire to see whether there might be any marvelous thing within."

Leonardo's earliest dated drawing is a study of the Arno valley, strongly emphasizing its geological features. His notebooks contain landscapes with a wealth of geological observation from the regions of both Florence and Milan, often including atmospheric effects such as a heavy rainstorm pouring down on a town at the foot of a mountain range.

It had been observed for many years that strata in mountains often contained bands of sea shells. Conservative science said that these could be explained by the Great Flood described in the Bible. Leonardo's observations convinced him that this could not possibly be the case.

And a little beyond the sandstone conglomerate, a tufa has been formed, where it turned towards Castel Florentino; farther on, the mud was deposited in which the shells lived, and which rose in layers according to the levels at which the turbid Arno flowed into that sea. And from time to time the bottom of the sea was raised, depositing these shells in layers, as may be seen in the cutting at Colle Gonzoli, laid open by the Arno which is wearing away the base of it; in which cutting the said layers of shells are very plainly to be seen in clay of a bluish colour, and various marine objects are found there.

This quotation makes clear the breadth of Leonardo's understanding of geology, including the action of water in creating sedimentary rock, the tectonic action of the Earth in raising the sea bed and the action of erosion in the creation of geographical features.

In Leonardo's earliest paintings we see the remarkable attention given to the small landscapes of the background, with lakes and water, swathed in a misty light. In the larger of the ''Annunciation'' paintings is a town on the edge of a lake. Although distant, the mountains can be seen to be scored by vertical strata. This characteristic can be observed in other paintings by Leonardo, and closely resembles the mountains around Lago di Garda and Lago d'Iseo in Northern Italy. It is a particular feature of both the paintings of '' The Virgin of the Rocks'', which also include caverns of fractured, tumbled, and water-eroded limestone.

Cartography

In the early 16th century maps were rare and often inaccurate. Leonardo produced several extremely accurate maps such as the town plan of Imola created in 1502 in order to win the patronage of Cesare Borgia. Borgia was so impressed that he hired him as a military engineer and architect. Leonardo also produced a map of Chiana Valley in Tuscany, which he surveyed, without the benefit of modern equipment, by pacing the distances. In 1515, Leonardo produced a map of the Roman Southern Coast which is linked to his work for the Vatican and relates to his plans to drain the marshland.

Recent research by Donato Pezzutto suggests that the background landscapes in Leonardo's paintings depict specific locations as aerial views with enhanced depth, employing a technique called cartographic perspective. Pezzutto identifies the location of the ''Mona Lisa'' to the Val di Chiana, the ''Annunciation'' to the Arno Valley, the '' Madonna of the Yarnwinder'' to the Adda Valley and '' The Virgin and Child with St Anne'' to the Sessia Valley.

Hydrodynamics

Leonardo wrote:

All the branches of a water ourseat every stage of its course, if they are of equal rapidity, are equal to the body of the main stream.

Among Leonardo's drawings are many that are studies of the motion of water, in particular the forms taken by fast-flowing water on striking different surfaces.

Many of these drawings depict the spiralling nature of water. The spiral

HOME


Content is Copyleft
Website design, code, and AI is Copyrighted (c) 2014-2017 by Stephen Payne


Consider donating to Wikimedia



As an Amazon Associate I earn from qualifying purchases