Leonardo Da Vinci’s Madonna of the Carnation

Leonardo Da Vinci’s Madonna of the Carnation is currently displayed in the Alte Pinakpthek gallery in Munich, Germany. This rendition of the Madonna and Child was originally thought by art historians to have been painted by Andrea del Verrocchio; however, it is now agreed that Da Vinci created this piece. An oil painting on panel, the Madonna of the Carnation made use of a new medium of the Renaissance. This painting depicts Mary sitting with an exceedingly chubby and somewhat disproportionate baby Jesus on her lap. She holds a carnation, a symbol of healing, in her left hand. Da Vinci illuminates the faces of Mary and the Child but darkens the background through shadowing using the technique of chiaroscuro, which he later masters. The baby Jesus is looking upwards while Mary is looking down – neither are looking at the other. The folds and shadowing of their clothes are suggestive of depth, and the background of mountains and the blue sky adds to this feeling as the background becomes blurred in the distance, melding into the horizon.

Sources Used:

Feinberg, Larry J. “Sight unseen: vision and perception in Leonardo’s Madonnas: in the first of two articles on Leonardo da Vinci, Larry J. Feinberg explains how the artist’s interest in the way the eyes work influenced his realistic depictions of the Christ Child as a baby learning to see.” Apollo 159.509 (2204): 28-34. GALE. Web. 28 Feb. 2018.

“Madonna of the Carnation.” Wikipedia. Wikimedia Foundation, 24 Nov. 2016. Web. 28 Feb. 2018.

Image Courtesy of Wikipedia, page titled Madonna of the Carnation. Image is Public Domain.

Da Vinci's Cannons

Leonardo Da Vinci was living in a world engulfed in war, having been born just after the Hundred Year's War, and living through the beginning of the Spanish Italian Wars in 1494. As a self-proclaimed weapons designer, Da Vinci was fascinated with improving upon and developing new ways to destroy an enemy. In his notebooks, there are over 10 designs for different siege weapons, cannons, and guns, many of which are reproduced and on display in Italy, designed from the original sketches in the Codex Atlanticus. Such weapons include his three-barreled cannon, 33-barreled organ, and his varieties of elevating gear cannons.  The primary focus of these weapons was to inflict as much damage possible through a machine that was easier to operate and more effective than previous light artillery of the time. For example, the Da Vinci Museum of Science and Technology describes his triple barrel cannon as being, "...a different specimen of light artillery: the gun carriage is easy to handle and it has three front-load guns. To improve firing accuracy, the three guns can be adjusted in height by means of a peg mechanism. (The Collection of Models)" This type of adjustment and agility is revolutionary in that it allows the user to not only fire 3 shots at once, but also be able to precisely aim without a team of multiple men. His two very similar single barrel cannon designs also involve a precise aiming system of either pegs or screws.

Sources:

John. “Bensozia.” Leonardo's Cannon, 1 Jan. 1970, benedante.blogspot.com/2011/06/leonardos-cannon.html.

in History, Technology | April 7th, 2016 3 Comments. “Leonardo da Vinci Draws Designs of Future War Machines: Tanks, Machine Guns & More.” Open Culture, www.openculture.com/2016/04/leonardo-da-vinci-draws-designs-of-future-wa....

“Triple Barrel Canon.” Leonardo da Vinci's Triple Barrel Canon Invention, www.da-vinci-inventions.com/triple-barrel-canon.aspx.

“The collection of models.” The collection of models - museoscienza, www.museoscienza.org/english/leonardo/models/.

Central Plan Churches

Although there is no evidence that any of Da Vinci’s church designs were actually constructed, he sketched many floorplans and elevations in his notebooks. Most of these sketches experimented with a central-plan design, where all outside rooms were centered around a main room. His church floor plans usually featured a square or circular center room with semi-circle or square rooms surrounding them.  Da Vinci utilized his mathematical background profusely in his floor plans, experimenting with the proportions of each room as well as symmetrical and asymmetrical designs. In one of his prominent designs, a Greek cross with equally sized legs outlined the center of the church used for mass. Many of Da Vinci’s sketches were done in the 1480s, and were probably influenced by Filippo Brunelleschi, a prominent Italian architect who also used central-plan designs in his churches.

Sources: Xavier, Joao. “Leonardo’s Representational Technique for Centrally-Planned Temples.” Reasearch Gate, Jan. 2008, www.researchgate.net/figure/Leonardo-da-Vinci-Drawing-of-churches-MS-BN-....

Phillips, Cynthia. “101 Things You Didn't Know about Da Vinci.” Google Books, books.google.com/books?id=qvpFDwAAQBAJ&pg=PA106&lpg=PA106&dq=da%2Bvinci%2Bchurch%2Bcross%2Bdesign&source=bl&ots=XuVDtCOeBM&sig=c47NhxgS09TO-7bLu4KRTIH3Cyk&hl=en&sa=X&ved=0ahUKEwjykczD5NjZAhXC7oMKHQ9ZAN0Q6AEIPzAH#v=onepage&q=da%20vinci%20church%20cross%20design&f=false.

Teodoro, Francesco Di. “Leonardo Da Vinci: The Proportions of the Drawings of Sacred Buildings in Ms. B, Institut De France.” Architectural Histories, Ubiquity Press, 7 Jan. 2015, journal.eahn.org/articles/10.5334/ah.cf/.

Image Source: Wikimedia Commons: 

https://upload.wikimedia.org/wikipedia/commons/8/8f/Leonardo_da_vinci%2C_Study_of_a_central_church.jpg

Linear Perspective

The Adoration of the Magi Perspectival Study

During the Renaissance in Italy, artist and architects sought to understand how to more accurately portray three dimensional objects in a flat plane. This led to the development of linear perspective, a system of creating the illusion of depth through the use of lines that converge at a single vanishing point on the horizon line. As an apprentice in Andrea del Verrocchio’s studio, Leonardo was introduced to the rules of perspective through De Pictura, a treatise on perspective written by the Italian architect Leon Battista Alberti in 1435. One of the clearest uses of linear perspective in Renaissance art is seen in da Vinci’s perspectival study for The Adoration of the Magi. This piece reflects da Vinci’s approach to creating a three-dimensional space on a flat plan and demonstrates his mastery of linear perspective. 

Sources

Blumberg, Naomi. “Linear Perspective.” Encyclopedia Britannica, Encyclopedia Britannica, Inc. , 17 Mar. 2016, www.britannica.com/art/linear-perspective.

“Da Vinci - The Artist: A True Master of His Craft.” Museum of Science, Museum of Science, Boston, 2018, www.mos.org/leonardo/artist.

Image Retrieved from Wikimedia Commons, fair use

Ornithopter

Leonardo Da Vinci was very interested in the possibility of flight for humans, which explains his extensive study on birds and their ability to fly. This was highlighted through his Codex of Flight of Birds. Though there were extensive drawings on a human-powered flying contraption, called the Ornithopter,  Da Vinci soon came to the conclusion that humans themselves were not powerful enough to support the lift-off of the machine nor were they strong enough to support the machine through the flight. However, the device in itself was brilliant because it modeled the human to be positioned such that center of gravity would enable flight and the wings flapped using a pedal, rod, and pulley system. Lastly, we believe that the machine was also extensively tested for flight, through evidence from his associates however there is no evidence of the creation of the machine itself.

Sources:-

“Flying Machine.” Leonardo da Vinci's Flying Machine Invention, www.da-vinci-inventions.com/flying-machine.aspx.

FLYING MACHINES - Leonardo da Vinci, www.flyingmachines.org/davi.html.

Fuller, John. “Top 10 Bungled Attempts at One-Person Flight.” HowStuffWorks Science, HowStuffWorks, 8 Mar. 2018, science.howstuffworks.com/transport/flight/classic/ten-bungled-flight-attempt2.html.

 Image Courtesy:- Wikimedia Commons, public domain

https://commons.wikimedia.org/wiki/File:Design_for_a_Flying_Machine.jpg

Anemometer

The usage of simple instruments to indicate the direction of the wind has been known since before the Middle Ages. Leon Battista Alberti developed the anemometer in 1450 to measure wind velocity. However, Leonardo da Vinci redesigned the device, making it more accurate and easier to measure wind force. The anemometer functions because a piece of wood is attached to a frame and gets raised by the wind flowing across the contraption. A scale is labeled on the frame and based on the highest location achieved by the moving piece of wood, a relatively accurate measurement of wind force can be determined. Later versions of the anemometer included applications of fluid dynamics, where wind pressure resulted in a liquid column travelling up a tube and the distance traveled being related to wind force. Another style of anemometer by Thomas Robinson in 1845 included a revolving contraption that spun freely in the wind and wind velocity being able to be determined based on the number of revolutions per unit of time.

Sources:

“Anemometer.” Leonardo Da Vinci's Anemometer Invention, 2008, www.da-vinci-inventions.com/anemometer.aspx.

“Windvanes and Anemometers.” Multimedia Catalogue, 2010, https://brunelleschi.imss.fi.it/museum/esim.asp?c=500005.

Image Source : Permission to use by Fondazione Museo Nazionale della Scienza e della Tecnologia Leonardo da Vinci - via San Vittore, 21 - 20123 Milano (Italia). “Anemometer - Leonardo Da Vinci.” Museoscienza, 2018, www.museoscienza.org/english/leonardo/models/macchina-leo.asp?id_macchina=20.

Leonardo Da Vinci’s Virgin of the Rocks

Leonardo Da Vinci named two of his paintings the Virgin of the Rocks, and these paintings both depict the Madonna and Child with only a few significant details altered. The earlier version is displayed in the Louvre in Paris while the later version hangs in the National Gallery in London. They are both around the same size, 2 meters, and the are both painted using oil on wooden panels, though the version hanging in the Louvre has since been transferred to a canvas. Both paintings depict the Madonna and Child alongside an angel and an infant John the Baptist. The rocky landscape lends to the title of the two pieces. The paintings differ in a variety of minor ways including the techniques of color, lighting, and sfumato. The version hanging in the Louvre is generally considered the earlier painting, and it was likely painted from around 1483 to 1486. This version is regarded as a perfection of the sfumato technique which Da Vinci is known for. The version hanging in London has a less precise date ascribed to it, but it was likely painted before 1508. The main differences between the two paintings are the positioning of the angel, the coloring of the robes, the halos (or lack thereof), and the staff of John the Baptist (or lack thereof).  

Sources used:

Pizzorusso, Ann. "Leonardo's Geology: The Authenticity of the 'Virgin of the Rocks.'" Leonardo 29.3 (1966) 197-200. JSTOR. Web. 28  Feb. 2018. 

“Virgin of the Rocks.” Wikipedia. Wikimedia Foundation, 7 Feb. 2018. Web. 28 Feb. 2018.

Image Courtesy of Wikipedia, page titled Virgin of the Rocks. Image is Public Domain.

Giant Crossbow

Leonardo da Vinci is widely known for his many engineering designs centuries before anyone else came up with similar ideas. He was a respected artist and inventor, but also was a gifted military engineer. Something that he really understood was the psychological impact of weaponry. Da Vinci came up with several versions of a giant crossbow, comprised of winding gears similar to the compound longbow of today. When his sketches came to life on the battlefield, they spanned 27 yards across. Each device had six wheels for stability and mobility, and the crossbow itself was made of thin, flexible wood. Priming the giant crossbow involved cranking back various gears and loading up the artillery, and any projectile was launched by releasing a holding pin by striking it with a mallet. The crossbow invention appeared to be made to launch large stones or flaming bombs rather than oversized crossbow bolts, which makes it clear that da Vinci meant for this military invention to cause fear amongst enemies rather than merely inflict mass damage and chaos.

Sources:

“Giant Crossbow.” Leonardo Da Vinci's Giant Crossbow Invention, 2008, www.da-vinci-inventions.com/giant-crossbow.aspx.

“Leonardo - Giant Crossbow.” BBC Science & Nature, 2014, www.bbc.co.uk/science/leonardo/gallery/crossbow.shtml.

Image Source : Leonardo da Vinci (https://commons.wikimedia.org/wiki/File:Leonardo_da_vinci,_Giant_Crossbo...), "Leonardo da vinci, Giant Crossbow", marked as public domain, more details on Wikimedia Commons: https://commons.wikimedia.org/wiki/Template:PD-old.

Da Vinci's Ideal City

Leonardo DaVinci Ideal City, www.leonardo3.net

Leonardo was known to dislike the state of urban living, describing cities as old fashioned, where people lived crammed together "like a herd of goats." After Filarete's project Sforzinda, Leonardo was also fascinated by the idea of creating a complex, perfect city. The design combines Da Vinci's wide range of talents, and shows his mastery of architecture, engineering, and art. The phrase ideal city refers to perfection of the 'machinery' of the city. His design utilized his invention of locks to make waterways efficient while keep the city's inhabitants safe from violent floods of water. There was also a strong emphasis on hygiene in his design, which included mechanisms for keeping the streets clean as well as preventing water and waste to stagnate. Da Vinci mentions that he believes the city should be cleaned at least once a year. His city's transportation network included different level streets for different purposes of transportation. Overall, his design focused on the possibilities of geometrically perfect solutions to the predicaments of urban life. 

Sources:

“The ideal city – Ms B Fol 16r and 37.” Universal Leonardo, University of Arts, London, www.universalleonardo.org/work.php?id=519.

“The Ideal City.” Museoscienza, Museo Nazionale della Scienza e della Technologia "Leonardo DaVinci", www.museoscienza.org/english/leonardo/invenzioni/citta.asp.

Image Source: "The Ideal City", www.leonardo3.net

Leonardo Da Vinci’s Madonna Litta

Leonardo Da Vinci’s Madonna Litta is currently housed in the Hermitage Museum in Saint Petersburg, Russia. This painting depicts Mary holding Christ as he is breastfeeding. In his left hand the baby Christ holds a little goldfinch which is representative of his future Passion. The painting is within an architectural space which has two arched windows in the background. There is little light within the painting (possibly an attempt towards mastering the technique of chiaroscuro) which make the blue background outside of the windows even more apparent. The windows also display Da Vinci’s technique of sfumato, which allows for a more realistic depth of background in which further away objects become less distinct and blend into the horizon. This painting has been attributed to Da Vinci because within his Codex Vallardi, which is currently housed in the Louvre, there is a metal point drawing of a woman’s face in a near profile which is exceedingly similar to the woman’s face in the Madonna Litta.

Sources Used:

Clark, Kenneth. "The Madonna in Profile." The Burlington Magazine for Connoisseurs 62.360 (1933): 136–140. JSTOR. Web. 28 Feb. 2018.

“Madonna Litta.” Wikipedia. Wikimedia Foundation, 20 Dec. 2016. Web. 28 Feb. 2018.

Image Courtesy of Wikipedia, page titled Madonna Litta. Image is Public Domain.

Fasiculus Medicinae

Fasciculus Medicinae is considered the first printed illustrated medical book. It was published in 1491 by a printing company in Venice. The author of the book is Johannes de Ketham. The book is a compliation of multiple essays written about clinical medicine. 8 subjects are discussed in Fasciculus Medicinae: urine and uroscopy, phlebotomy, judgements of the veins, phlebotomy based on the zodiac, women’s health, surgery, and anatomy. The book contains six woodcut illustrations. The first edition of the book was in Latin and a second edition was translated into Italian and then into vernacular Italian in 1493. Leonardo Da Vinci used the Italian edition of Fasciculus Medicinae as a guid during his dissections and as a source of medical knowledge. Fasciculus Medicinae would be further edited through time to improve illustrations and organization. In addition to this more essays and four new illustrations would be added.

Source:

Dimaio, Salvatore, Federico Discepola, Rolando F. Del Maestro. Il Fasciculo Di Medicina of 1493: Medical Culture Through the Eyes of the Artist. Neurosurgery 2006, 58:187-196. DOI:10.1227/01.NEU.0000192382.37787.80. Accessed March 8, 2018.

Image Source:

Wikipedia

Coefficient of Friction & Wear

Some of da Vinci’s early work in bearing design centered on the shortcomings of existing designs. He began his work with a series of studies exploring the interaction between objects in contact with one another. The experimental equipment da Vinci designed was an innovation in and of itself. Da Vinci studied what factors contributed to friction and correctly concluded that friction is influenced not only by the types of materials in contact, but also the contact area of the two objects. To decrease friction, Leonardo suggested the use of rollers as well as lubricants between sliding surfaces.

From this work, da Vinci fathered the concept of a “coefficient of friction.” Da Vinci used a value of 0.25 for the coefficient of friction between two “polished” surfaces, which is impressively close to estimates used today (500 years later). This feat is even more impressive due to the mathematical complexity of determining coefficients of friction between nonlubricated surfaces even today.

Alongside friction, da Vinci was also interested in wear (a result of friction). In his day, mechanical objects experienced severe wear and either required frequent maintenance or replacement to maintain functionality. Da Vinci experimentally determined that the direction of wear depended on the load, and was not always vertically downwards, as was previously believed. His experiments also yielded that lubrication alone was insufficient to prevent wear. This led him to investigate the value of rolling elements.

Source: 

Image: http://www.tribonet.org/wiki/friction-coefficients-in-atmosphere-and-vac...

Da Vinci's Scientific Approach to Bearings

Work done by da Vinci both to understand friction and to design devices to overcome it were documented in his notebooks written between 1493 and 1497. He made observations on principles such as wear and coefficient of friction. These observations led him to understand the value of lubrication, cages, and the impossibility of perpetual motion.

Most of what is known regarding da Vinci’s work on ball bearings comes from the Codex Madrid I. These works were found in 1967 and were written by da Vinci between 1493 and 1497. Previously, scholars had the Codex Atlanticus, which was a more random collection of writings and sketches created between 1483 and 1518. Material in the Codex Atlanticus is considered as drafts upon which da Vinci expanded and improved in Codex Madrid I.  

In these notebooks, da Vinci makes observations and predictions of system interactions that are not far off from the empirical values still used by tribologists today. The designs he proposes are novel and truly innovations that greatly influenced designs that are still considered the most efficient bearing designs today. 

Source: Reti, Ladislao. “LEONARDO ON BEARINGS AND GEARS.” Scientific American, vol. 224, no. 2, 1971, pp. 100–111., www.jstor.org/stable/24927729.

Image: http://ebooks.library.cornell.edu/k/kmoddl/toc_leonardo1.html

The Italian Wars

Beginning in 1494, King Charles VIII of France launched an invasion of the Italian peninsula. During this time, France had already begun the transition from a semifeudal state to a nationstate, shifting France away from the medieval period toward the renaissance. Upon crossing the Alps, the French army had a significant advantage over the Italians. Their cavalry and infantry were accompanied by small, light mobile artillery that would ensure their victory. The main strategy of the Italian people was to use their heavy walls and fortifications to withstand enemy invasion. However, because of the superior firepower and effective use of cannons by the French, they were able to conquer the Italian cities with ease. The French cannons were far superior to the cannons of the Italians, which were outdated and primitive. The light, cast bronze cannons could be shot quickly and easily, making them effective for destroying walls and terrorizing the Italian population. Because of new gunpowder-fueled siege weaponry, specifically culverins and bombards, the medieval strategy of building fortresses was proving to be obsolete. The significant advancements in cannons and firearms would force the world to redesign cities and defenses, drastically reinventing the way war is waged.

The invasion by Charles VIII was only the first of many invasions of Italy through the 16th century. As the Italian Wars continued for another 60 years, Italy was constantly under threat from both foreign and domestic powers. This ongoing war led to an economic downturn that severely hindered new art or great works in Italy. Not even the church could afford to commission new art. By 1516, Leonardo Da Vinci had already left Italy to find a more welcoming artistic environment in France. By 1527, the Spanish had conquered Rome, costing Italy its "political and individual freedom" (Ewhelan). Ultimately, this would be the beginning of the end of the Italian Renaissance and the beginning of the Counter-Reformation. 

Sources:

The Editors of Encyclopædia Britannica. “Italian Wars.” Encyclopædia Britannica, Encyclopædia Britannica, inc., 4 Mar. 2016, www.britannica.com/event/Italian-Wars.

“Italian Wars.” Wikipedia, Wikimedia Foundation, 21 Feb. 2018, en.wikipedia.org/wiki/Italian_Wars.

Ruggiero, Guido. The Renaissance in Italy: a social and cultural history of the Rinascimento. Cambridge Univ. Press, 2015.

The Italian Wars, 1494-1559, www.historyofwar.org/articles/wars_italian_wars.html.

“What was the impact of Charles VIIIs invasion of Italy (1494) on the Renaissance?”  - DailyHistory.Org, dailyhistory.org/What_was_the_impact_of_Charles_VIIIs_invasion_of_Italy_(1494)_on_the_Renaissance%3F.

Ewhelan. “Why did the Italian Renaissance End?” Why did the Italian Renaissance End? - DailyHistory.Org, dailyhistory.org/Why_did_the_Italian_Renaissance_End%3F.

St. Mark's Clocktower

St. Mark’s Clocktower, located on the Piazza San Marco in Venice, Italy, is an architectural representation of an analog and digital clock with the added embellishments of a Madonna and child, a winged lion, the symbol of Venice, and a bell which two bronze statues (the Moors) ring. The Madonna and Child are made of bronze, and they rest above the analog clock, seemingly looking down over time and space. Space is included in this clock because of the use of the zodiac signs on the clock face, as well as the representation of the Ptolemaic universe in which the sun rotates around the Earth (though the Earth has since been removed from the clock as the Copernican theory of space has become accepted). The Madonna and Child harken back to the Byzantine ideals of anagogic space, and twice a year, at Epiphany and on Ascension Day, the three Magi appear from a doorway which is usually covered by panels displaying a digital clock face. These three Magi, led by an angel, proceed across the clock face and bow to the Madonna and Child. This procession was broken for a long period of time following construction, but in a series of repairs led by Bartolomeo Ferracina from 1757 to 1759, their sequence was fixed. On top of this, the digital clock from which these three magi emerge was also a part of a restoration and enhancement project. In an effort led by Luigi de Lucia from 1858-1866, panels were made in the doorways next to the Madonna and Child which displayed the hour on the left and the minutes on the right, changing every five minutes. One interesting detail about the placement of the Madonna and Child as opposed to the winged lion, is that the lion is raised higher than the other figures, thus implying a sort of superiority of state over religious symbology. 

Sources used:

Muraro, Michelangelo. “The Moors of the Clock Tower of Venice and Their Sculptor.” The Art Bulletin 66.4 (2014): 603-609. College Art Association. Web. 28 Feb. 2018.   

“St. Mark’s Clocktower.” Wikipedia. Wikimedia Foundation, 25 Jan. 2018. Web. 28 Feb. 2018.

Image provided courtesy of http://www.planetware.com/venice/st-marks-square-i-vn-vpsm.htm 

Designs Enabled by Ball Bearings

Da Vinci’s work on ball and roller bearings was hugely useful in helping him to design other larger inventions. With his knowledge of the advantages of bearing use and design of to improve their implementation he was able to create many other novel inventions which would not have been possible if only sliding contacts were used.

For example, both da Vinci’s self-propelled cart as well as his armored car (tank) would not have been possible without bearings. In his armored car, there were a number of cannons mounted to a circular platform that could rotate 360 degrees. The rotation of a large and heavy platform could only be made possible via the use of rolling element bearings. Similarly, his sketches of a self-propelled cart relied heavily on bearings. In 2006 when scholars built a model of the cart based on his sketches, it was able to work. Again, this was enabled by ball bearings.

Many others of Leonardo da Vinci’s inventions made use of bearings as well. Almost every design that included two contacting elements moving relative to each other was improved and made more possible thanks to improvements in bearing design via race ways and cages as well as lubrication. Designs such as da Vinci’s flying machine, while not feasible due to weight to lift ratio limitations, was still improved via the incorporation of bearings. His robotic knight, like many modern robots, contained several moving parts who’s motion was made easier and less resource intensive due to bearings.

Today the uses of bearings are limitless. They can be found in simple toys such as fidget spinners as well as complex, high speed manufacturing lines and autonomous robots.

Sources: 

Image: http://www.leonardodavincisinventions.com/war-machines/leonardo-da-vinci...

Clock

Leonardo da Vinci wrote about a clock design that was more accurate than the clocks of his time in his book, Codex Atlanticus. He did not invent the clock, but he did make improvements to the current design. Da Vinci’s clock had two separate mechanisms for both minutes and hours, comprised of weights, gears, and harnesses. There was also a dial that kept track of changing moon phases, and he incorporated diamonds and rocks in the design. The biggest change from the conventional clock of the time was that da Vinci utilized springs instead of weights to operate his clock. However, his design was never brought to fruition. By the 17th century, pendulums were incorporated into clock design and brought new innovation to traditional clock design.

Sources:

“Clock.” Leonardo Da Vinci's Clock Invention, 2008, http://www.da-vinci-inventions.com/clock.aspx.

“Clock.” LEONARDO DA VINCI'S INVENTIONS AND IDEAS, www.leonardo-davinci-inventions.weebly.com/clock.html.

Image Source : Leonardo da Vinci (https://commons.wikimedia.org/wiki/File:Leonardo_da_Vinci_dial_of_Venus.jpg), "Leonardo da Vinci dial of Venus", marked as public domain, more details on Wikimedia Commons: https://commons.wikimedia.org/wiki/Template:PD-old.

Clock Mainspring

In the first decade of the 16th century, a German locksmith from Nuremberg named Peter Henlein began using springs to power clock mechanisms. Winding the “mainspring” stored energy, which was slowly released over time, turning the hand of the timepiece. Because spring could be made much smaller and stiffer than a traditional verge escapement mechanism, the weight and size of Henlein’s timepieces were significantly reduced. This breakthrough led the clock from being a tower-sized mechanism in the center of town to a small pocket- or wall-sized device that wealthy gentlemen could carry around with them throughout the day. However, these early mainspring watches still had their faults. Naturally, the clock would run faster initially, when the spring was tightly wound, and slow down as the spring became loose. Later, a solution to this problem, the “fusee” was developed to release the tension of the spring over time more evenly. The ability of an individual to have access to a relatively accurate timepiece anywhere they went had a significant impact on the daily lives of people in 16th century Europe, allowing activities throughout the day to be recorded with more precision than ever before.

Sources: “Spring Driven Clocks.” 2018. https://www.merritts.com/merritts/library/spring_driven_clocks.aspx. Accessed 8 Mar 2018.

Bellis, Mary. “Spring-Powered Clocks.” The History of Mechanical Pendulum Clocks and Quartz Clocks. 7 April 2017. https://www.thoughtco.com/history-of-mechanical-pendulum-clocks-4078405. Accessed 8 Mar 2018.

Image: Wikipedia Commons, Public Domain. https://commons.wikimedia.org/wiki/File:Alarm_clock_mainspring.JPG.

Arno River Project

Arno River

Da Vinci’s watermill wasn’t his only attempt to control the flow of water. One of his most ambitious projects was an attempt to construct a channel and a dam to divert the river Arno away from Pisa so that the city could no longer cut off Florentine trade. The plan was made in conjunction with another historically significant Florentine, Niccolo Machiavelli. Da Vinci for the project, designed not only the dam and channel, but also many machines intended to assist in construction. Unfortunately, as was so often the case of Leonardo, he was ahead of his time, and Florence simply did not have the resources to conduct a project on this scale. While theoretically feasible, it wasn’t economically feasible. While the project never came into fruition, the notion of controlling the flow of a river would live on past Leonardo, and would, eventually, succeed.

https://leonardodavinci.stanford.edu/submissions/dgill/FinalProject/Leon...

Image from Wikimedia Commons, Public Domain

Renaissance Painting Techniques

Madonna del Prato by Raphael

The Renaissance brought about a new tradition in the field of art. Artists sought to achieve a greater sense of realism and naturalism in their paintings, as opposed to the rigid and stylized characteristics of the preceding medieval and byzantine periods. Artists were aided in achieving this goal in part through the development of oil paint, which in turn gave rise to the development of new painting techniques. The most important techniques that were established during the renaissance were sfumato, chiaroscuro, perspective, foreshortening and proportion. The advent of these techniques marked a significant shift in art history. Sfumato, a term coined by Leonardo da Vinci, refers to the subtle blending of colors and the blurring of sharp lines. Chiaroscuro is the use of strong contrast between light and dark to create depth. Perspective, foreshortening and proportion all relate to the use of mathematical principles to establish lines used to create the illusion of depth. Used in combination, these techniques greatly contributed to an artist’s ability to create three dimensional figures on a two-dimensional plane.

Sources

Gombrich, E. H. Art and Illusion: A Study in the Psychology of Pictorial Representation.

Princeton University Press, 1960.

Wikipedia, the free encyclopedia. “Renaissance Art.” Wikipedia, Wikimedia Foundation, Inc. , 6

Mar. 2018, en.wikipedia.org/wiki/Renaissance_art#Techniques.

Image Retrieved from Wikimedia Commons, fair use

The da Vinci Glow

da Vinci Earthshine

Leonardo da Vinci was known for many things; art, architecture, weapons, and anatomy. He is rarely thought of for his work in astronomy. He had a great interest in the moon and its relationship to the Earth and the sun. One of his most interesting achievements in the field of astronomy was his understanding of earthshine. After sunset on a night with a crescent moon, an ashen glow appears on the surface of the moon, the section of the moon which is in Earth’s shadow lights up faintly, and for thousands of years no one could explain how part of the moon was still slightly illuminated when there was no apparent light source acting on it. Leonardo was intrigued by the phenomenon and set out to discover the answer behind the mystery. He spent many hours  studying and observing the moon, and then he finally had a breakthrough. It was because of the Earth! He came to the conclusion that the light coming from the sun would reflect onto the oceans of the earth, and in turn create an ashen glow on the moon itself. Leonardo had previously determined that the moon had an atmosphere and bodies of water on it, this would make the moon a great reflector of light, meaning that even a small amount of light creates some kind of reflection of light off of the darkest part of the moon.

Source: "The Da Vinci Glow." NASA. 4 Oct. 2005. https://science.nasa.gov/science-news/science-at-nasa/2005/04oct_leonardo. Accessed 27 Feb. 2018.

Image source: NASA. Public Domain. https://science.nasa.gov/science-news/science-at-nasa/2005/04oct_leonardo.

Death of Marcantonio della Torre

Leonardo da Vinci originally planned to publish his anatomical notes in the form of a book. In this endeavor he had the support of Marcantonio della Torre, a professor at the University of Padua who shared da Vinci's interest in dissections and human biology. However, Marcantonio's life was cut unexpectedly short by the plague, an event that severely curtailed da Vinci's attempts to publish his notes. Coupled with political turmoil in Italy that following year, it spurred da Vinci's relocation to France, and the eventual ending of any of his attempts to bring his anatomy work to the general public.

Source:
"Marcantonio della Torre." https://en.wikipedia.org/wiki/Marcantonio_della_Torre.

Image source: https://commons.wikimedia.org/wiki/File:Marc_Antonio_della_Torre_(Turrianus)._Line_engraving,_1688._Wellcome_V0005857.jpg

The Copernican Model

Copernican Model

Nicolaus Copernicus was born on Feb. 19, 1473 in Poland. At the age of 10, his father died, leaving him to be cared for by his uncle who oversaw his education. At the age of 18, he traveled to Italy to attend college where he intended to study the laws and regulations of the catholic church and become a canon. He instead spent a majority of his time studying mathematics and astronomy. While away at school, his uncle was elevated in his church to the position of Prince-Bishop of Warmia which gave him the opportunity to place Nicolaus in the Warmia canonry. After 7 years, he earned a doctorate in canonry and law, but remained more interested in astronomy. During his time at the University of Bologna, he lived and worked under astronomy professor Domenico Maria de Novara. When he returned home and was able to live in a tower which had an observatory that he looked through in his spare time. During many hours observing the night sky, he began to question the theory that had been proposed by Aristotle and Ptolemy 1400 years earlier. This theory was that of the Ptolemaic system, in other words, a geocentric universe. He first noticed some striking problems with the mathematics of the system, the paths of the celestial bodies were too complex and sometimes the planets would travel backwards. Astronomers call this “retrograde motion” and Ptolemy accounted for this by incorporating circles inside other circles,  known as eclipses. Unfortunately these paths were too complicated to have occured naturally, so Copernicus eventually doubted the system as a whole. He finally determined that the earth’s motion in space creates the retrograde motion of the other planets, the rotation of the earth on its own axis is what causes the rising and setting of the sun, and most importantly, the Sun is the center of the universe, not the Earth. With this conclusion he was able to simplify the paths of the planets and stars, determine the order of the planets, and create his own system, the Copernican system.

Sources: Redd, Taylor. "Nicolaus Copernicus Biography: Facts and Discoveries." Space.com. 19 Feb. 2013. https://www.space.com/15684-nicolaus-copernicus.html. 28 Feb. 2018.

Image source: Space.com. Public domain. https://www.space.com/15684-nicolaus-copernicus.html.

De Humanis Corpore

De humanis Corpore is an unpublished textbook Leonardo Da Vinci was working on for a large portion of his life. The textbook was planned to have been finished in 1516 CE but Leonardo Da Vinci never finished the book. It was planned to have 120 sections with extensive amounts of illustrations. The textbook was meant to explain each of the organs and apparatus’ of anatomy, physiology, and pathology in the human body. A section of the book was also going to be dedicated to a comparative discussion of human and animal anatomy. The textbook was largely finished and it is known that Leonardo employed two collaborators to organize the drawings (268 pages of anatomical drawings) and annotations he had wrote. It is theorized that Leonardo chose not to publish and finish his textbook due to being afraid of the textbook being too controversial for this time period. This theory was proposed because in his drawing of the heart and blood circulation Leonardo wrote “I could tell more, if I was allowed to do so.”

Source:

Sterpetti, Antonio V. The Revolutionary studies by Leonardo on blood circulation were too advanced for his time to be published. Journal of Vascular Surgery 2015, vol 62 (1): 259-263. DOI:https://doi.org/10.1016/j.surg.2015.10.001

Image Source:

Sterpetti, Antonio V. Anatomy and physiology by Leonardo: The hidden revolution?. Surgery 2016. Vol 159 (3): 675-687. DOI:https://doi.org/10.1016/j.surg.2015.10.001.