Leonardo da Vinci biography
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Leonardo da Vinci biography
Leonardo da VinciA painter, sculptor, architect, engineer, and scientist
Leonardo da Vinci (1452-1519), Florentine artist, one of the great masters of the High Renaissance. His profound love of knowledge and research was the keynote of both his artistic and scientific endeavors. His innovations in the field of painting influenced the course of Italian art for more than a century after his death, and his scientific studies - particularly in the fields of anatomy, optics, and hydraulics - anticipated many of the developments of modern science.
Paintings
Leonardo produced a relatively small number of paintings, but he was an extraordinarily innovative and influential artist;
his well-known paintings: The Adoration of the Magi, The Last Supper, The Mona Lisa, Leonardo's most famous work, is as well known for its mastery of technical innovations as for the mysteriousness of its legendary smiling subject;
Sculptural and Architectural Drawings
none of Leonardo's sculptural projects was brought to completion, but his approach to three-dimensional art can only be judged from his drawings.
none of his building projects was actually carried out as he devised them, but in his architectural drawings, however, he demonstrates mastery in the use of massive forms, clarity of expression, and especially a deep understanding of ancient Roman sources;
Scientific and Theoretical Projects
as a scientist Leonardo towered above all his contemporaries; his scientific theories, like his artistic innovations, were based on careful observation and precise documentation;
unfortunately, he never completed his planned treatises on a variety of scientific subjects; his theories are contained in numerous notebooks, most of which were written in mirror script; because they were not easily decipherable, Leonardo's findings were not disseminated in his own lifetime; had they been published, they would have revolutionized the science of the 16th century;
Leonardo actually anticipated many discoveries of modern times: in anatomy he studied the circulation of the blood and the action of the eye; he made discoveries in meteorology and geology, learned the effect of the moon on the tides, foreshadowed modern conceptions of continent formation, and surmised the nature of fossil shells; he was among the originators of the science of hydraulics and probably devised the hydrometer; his scheme for the canalization of rivers still has practical value; he invented a large number of ingenious machines, many potentially useful, among them an underwater diving suit; his flying devices, although not practicable, embodied sound principles of aerodynamics.
Leonardo's machines
Leonardo's output is the expression of the men and women of the time, of what they felt and did, of the machines they built so that in turn they could build churches, palaces, fortresses; machines for waging war, for work, for the manufacture and trade of all those goods whose availability was of such great importance to the rulers and their courts. Leonardo embarked upon his own path of research and drawing up of ideas and plans embracing a multitude of sectors, ranging from hydraulics to mechanics, to flight, to anatomy and to optics.. Flying Machines
ANEMOMETER
It is made up of a wooden graduated framework with a vane, which is turned by the wind so as to show its direction. This instrument was designed to study weather conditions, with a view to improving safety in human flight.
ANEMOSCOPE
Another flight instrument designed for indicating the direction of the wind. This is one of those devices, which Leonardo deemed necessary for human flight, in that they gave an insight into the characteristics of the air or the wind.
AERIAL SCREW
This is one of Leonardo's best-known designs. Some experts have identified it as the ancestor of the helicopter. Aerial screw would be made of reed, linen cloth and wire, with a diameter of 5 meters, operated presumably by four men who might have stood on the central platform and exerted pressure on the bars in front of them with their hands, so as to make the shaft turn. A machine thus designed would probably never have risen off the ground or been set moving; the idea remains, however, that if an adequate driving force were applied, the machine might have spun in the air and risen off the ground. The aerial screw differs from the other machines in that it was planned for the study of the propeller's tactile efficiency and not as a real flying machine. In the note accompanying the drawing, Leonardo, in fact, suggests that, by way of example, what he claims can be experimented by taking a thin, wide rod and rotating it fast in the air. This will prove that the arm of the person rotating the rod will be pulled upward towards the rod itself. In the same note, Leonardo suggests making a paper model of a screw and launching it by means of a coil spring wrapped around the base of the screw. The specific mentioning of the screw strengthens the assumption that this model was actually a representation of the windmill game, a toy that was already popular in Leonardo's age. Due to its small size, the toy could be operated by a spring or, better still, by a small rope, the fast unwinding of which turned the screw and made it move upward. This might be the source of the intuition that the same mechanism, larger in size and operated by an adequate driving force, could have risen off the ground. FLYING SHIP
Small flying ship equipped with flapping wings and helm.
This is one of the most imaginative flying machines conceived by Leonardo. The fliers' seats are located inside a shell-shaped vessel, which also housed all the mechanisms (screws, nut screws and cranks) controlling the two large bat-like wings. A particularly interesting detail is the ample plane in the tail area, most likely a system for adjusting the flying position and hence the direction of the ship itself. GLIDER WITH MANOEUVRABLE TIPS
While sensing the difficulties involved in accomplishing the great dream of flying with man-powered machines, Leonardo started to study gliding flight. In the glider designed by him, the flier's position is conceived in such a way as to allow him to balance himself by adequately moving the lower part of his body. The wings, an imitation of the wings of bats and of large birds, are fixed in their innermost section (closest to the person) and mobile in their outer section. The latter in fact can be flexed by the flier by means of a control cable maneuvered through handles. Leonardo had developed this solution after having studied the structure of birds' wings and having observed that the inner part of their wings moved more slowly than the outer part and that, therefore, the function of this part was to sustain rather than to push forward. INCLINOMETER
This instrument was used for controlling the air position of the flying machines devised by Leonardo. For the machine to reach the horizontal position indispensable for certain flight conditions, the small ball in the bell jar must be positioned right in the middle of the inclinometer. The bell glass is for preventing the wind from affecting the ball.
WING STRUCTURE
The wing structure study marked a critically important moment in Leonardo's endeavour to design a machine capable of making mankind fly. This is a bat-wise wing with a wood and cane frame covered with fabric stretched all over. The wing, with its veins and covering, is made up of a deal shaft with cane spokes leading off from it. PARACHUTE
In his notes, Leonardo remarks that, with a linen curtain shaped into a pyramid having a base 12 yards (about 7 metres) across and equally deep, if it is stiffly held open (anyone can jump from no matter what height without any risk whatsoever). As the length of the Florentine 'braccio' (yard) was about 60 cms., Leonardo's parachute can roughly be compared to a quadrangular pyramid having a base of about 7.20 metres and a height of the same size.
LEAF - SPRING ENGINE FOR FLYING MACHINE
This flying machine was designed to be driven by the mechanical power produced by a leaf spring, which was to drive the wings. This model is most interesting; in that it testifies to the fact that Leonardo was trying to fit the leaf-spring mechanisms in use for land machines to his flying devices. Not only that. The use of a leaf spring in place of human strength bears witness to Leonardo’s realization that human strength alone would hardly manage to make mankind fly. War Machines
CANNON WITH AN ADJUSTABLE ELEVATING ARC
This is a cannon whose elevation may be adjusted by means of a peg. It is one of the three firearms drawn by Leonardo on the same folio. Owing to its size, this cannon was destined to be used in field action by infantrymen. Besides having a light gun carriage mounted on wheels, this weapon can be adjusted in height by means of a peg blocking system. The cannon is front-loaded and has a bronze muzzle. SCYTHED CHARIOT
This is the framework of a scythed chariot. Already in use in Leonardo's day, this type of war machine was dusted down by Leonardo, who conceived of a few variations on the theme. The wheels of this horse-drawn chariot engage the scythes via gearing. As Leonardo put it, the scythes were capable of doing harm to friends and enemies alike. MACHINE FOR STORMING WALLS
Dusted off from the books of the past, this model depicts a war machine for storming walls. It is made up of a framework on wheels, fitted with an armored bridge, which leaning against the enemy walls and spanning across a moat, enables the assault troops to break into a city or a castle.
EIGHT-BARELLED ORGAN
This model illustrates a machine gun made up of a set of small-calibre muzzles mounted on one single wheeled carriage. Its elevation can be adjusted by means of a screw. The fan-wise arrangement of the muzzles, giving a longer firing range and a greater precision adjustment, helps facing the enemy charges. Thanks to its modest size, this weapon can be moved fast.
33- BARELLED ORGAN
This model of a machine gun consists of 33 small guns lined up in elevens, mounted on a single revolving framework. Once the first row of ammunition has been fired, the gunner can set up the second and the third rows one after the other. The muzzle-loading guns are hinged to the framework in order that they can swing upwards for loading. GIANT CROSSBOW
As an engineer and designer of offensive and defensive war machines, Leonardo did not neglect to consider traditional weapons, such as crossbows and catapults.
This crossbow was suggested as a major weapon of war and, in Leonardo's mind, it was to be employed for shooting large arrows against the enemy ranks and create havoc among them. In order to increase its flexibility and power, the gigantic bow was to be manufactured in several lamellar sections. The shooting rope was stretched with a mechanical device and was then released by percussion or through the action of a lever. The six carriage wheels could be inclined, so as to ensure greater firing stability. OGIVAL PROJECTILES
These models have been made to highlight Leonardo's remarkable intuition on the effect of air on projectiles fired by cannons. Although he did not develop a mathematical theory on trajectory, the wings and the particularly modern shape of the projectiles are grounds enough to assume that he had correct intuitions on the attrition action of the air and the importance of an aerodynamic shape to ensure trajectory stability and firing efficiency. AUTOMATIC IGNITING DEVICE
This model testifies to one of the ideas Leonardo developed in order to improve the ignition of firearms. The device is made up of a coil spring, linked to a wheel above by a chain. The wheel, rotating, strikes against the flint (on the left) and produces a spark. The trigger is on the right. The three-link Chain for automatic igniting device has been reproduced on a larger scale and built into a separate model. Water and Land Machines
DIVING BELL
Envisaging a diver’s prospective activities, Leonardo tried his hand at giving detailed descriptions of the outfit needed and of its workings. For usage at war, he conceived of simple head-coverings fitted with undersized snorkels, and of webbed gloves and flippers for a diver to wear.
DRILLING MACHINE
The double-movement drilling machine was conceived by Leonardo before his arrival in Milan. This machine made deep drilling and digging possible. It worked in the following way: the drill was driven into the ground by rotating the upper bar, while, by rotating the second bar, the drill was heaved back up without turning and it lifted out of the ground all the earth which had collected on it. BOAT WITH PADDLE WHEELS
Leonardo envisaged the driving paddle wheels of a boat being about 90 cm long. The wheels intended to magnify the oarsmen’s strength were designed as being about 60 cm in diameter, and fitted with 16 cogs that engaged with a sprocket wheel of about 15 cm in diameter fitted with 12 cogs.
According to Leonardo’s calculations - leaving aside all mechanical and nautical difficulties -, with a driving wheel making 50 rpm the boat would have sailed at 50 miles per hour.
THE GALATA BRIDGE
This model was made from the indications drawn from a very small drawing by Leonardo included in the Leicester manuscript. The drawing shows a plan and an elevation view of the bridge, which has a single span approximately 240 metres in length, 23 metres in width, with a peak height of 40 metres above the level of water. A unique feature is the double supporting structure at the head of the bridge shaped like the tail of a sparrow for the purpose of better bearing transversal thrust. A feature worthy of notice is the sketch of a masted ship, smoothly sailing under the central span of the bridge. WEBBED GLOVE
These gloves are designed for tying around the wrist. They are easy to wear and are probably made in leather with five wooden ribs to stiffen them out and make them resemble the feet of web-footed birds. These gloves are components of outfits designed for moving more smoothly in water. Work Machines
AUTO-FEED HYDRAULIC SAW
This model was reconstructed from a drawing illustrating an auto-feed water-powered saw. The hydraulic saw transmits alternating motion in quick succession to the blade and the carriage for holding the tree trunks. TEMPORARY BRIDGE ON TRESTLES
This machine belongs to Leonardo’s studies for the construction of temporary military bridges by means of tree trunks roped to each other. Leonardo explains how to arrange the trunks and to fasten them at an equal distance from one another. He also mentions the materials to use and reveals the tricks of the trade. The credentials Leonardo presented to the Duke of Milan, Ludovico il Moro, included this bridge and others of different kinds. BILGE PUMP
This machine was intended for pumping water out a galley’s bilge. The conical valve featuring in the pump was probably devised by Leonardo for a study of a water-fall bellows for smithies or foundries. REVOLVING BRIDGE
This is a model of one of the many "very light yet rugged" bridges. These bridges were designed for construction with material that was readily available and easy to transport. The bridge with a parabolic profile has only one span and is secured to the two banks by means of a large vertical pin. It is moved by means of ropes and hoists, aided by wheels and metal rollers in performing its sliding motion. Moreover, the bridge is equipped with a counterweight tank for balancing and manoeuvring purposes, while suspended in the air before being laid down on the opposite bank. DEEP - SEA DIVING SUIT
In Leonardo’s day, systems for working at a deep level underwater were already being studied. Leonardo devised a leather diving suit.
Cane hoses fixed together by leather joints enabled the diver to breathe. Steel spirals were inserted into the joints so as to prevent them from being crushed by the pressure of the water. The tubes used for breathing stuck out of the water and were held in place and protected by a dedicated floating device. CONTINUOUS COOLING DISTILLER
The characteristic feature of this alembic was a very broad condensing surface. The section in which the fire was produced was separated from the one containing the cooling water by a central section exposed to air. This system was designed to reduce the sudden change in temperature, which would damage the glass and ceramic containers. REVOLVING CRANE
This revolving crane, which had probably been seen by Leonardo on many construction sites, near stone quarries or at can excavation works, not only lifted weights but could also rotate, thereby allowing for the fast transfer of materials from one site to another. HYGROMETER
This instrument measures the moisture content of the air at the time the measurement is taken. A household name already in Leonardo’s day, it consists of scales that contain a hygroscopic substance (sponge, cotton wool) in one pan and wax in the other (wax does not absorb water.) On dry weather conditions, the scales mark zero. However, as the moisture in the air increases - and the weight of the hygroscopic substance rises accordingly -, the scales will tip towards the pan where the hygroscopic substance is.
SCREWTONGS
Leonardo applied the double screw principle to forging tongs to increase their gripping power. A large pair of tongs which are tightened by means of a screw and, further down, several trestles with a double screw tightening mechanism. DRILLING MACHINE
The double-movement drilling machine was conceived by Leonardo before his arrival in Milan. This machine made deep drilling and digging possible. It worked in the following way: the drill was driven into the ground by rotating the upper bar, while, by rotating the second bar, the drill was heaved back up without turning and it lifted out of the ground all the earth which had collected on it. DRIVE TRAIN DEVICE
A reduced friction between pivots and a gear intended to increase human power make this model an interesting example of a multi-faceted knowledge being applied to a single device. This “drive train for a cart”, in which power is transmitted to one wheel only, apparently anticipates the idea for the “differential gear”, which Leonardo highlighted in later drawings.
STUDY OF A FURNACE
This model shows a cutaway view of a twin-chambered furnace, which features a tall tower This furnace can have a tower as tall as you like, so long as it is filled with wood or coal in order that you do not have to be always there.
GOLDFORGING HAMMER
This is a hammer for forging precious metals - such as gold leaves - with the aid of synchronized movements actuated by weights. At each blow, a leaf is moved along automatically so as to receive the next blow. Leonardo also envisaged the possibility that a single source of motive power could operate several hammers at the same time. MACHINE FOR MAKING ROPES
The machine is composed of 15 bracket spools arranged in a semi-circle around a cylinder, positioned so that its axis is parallel to the primary threads to be twisted. The drum is made to rotate by means of a winch, so that the tension exerted on it is adequately balanced out. The spools are spun by thin ropes placed in an alternate manner to the left and to the right of the cylinder. The pin of each spool is held in place in a metal bracket secured to the base of the machine. The position and the tension of the rope are adjusted by means of a wedge placed nearby. MACHINE FOR MAKING MIRRORS
Model (a) depicts one of the machines for making concave mirrors with a short focal distance. The lever transmits a rotary motion both to the abrasive grinding disk and to the lens undergoing the grinding action.
The second machine (b) was designed for making both spherical and parabolic mirrors with a long curvature radius. The machine can simultaneously transmit a rotary motion to a bronze mirror and an alternating motion (backwards and forwards) to a circular copper section (abrasive disk). Pressure can be exerted on the moving abrasive section by applying a weight. This will produce the required curvature on the mirror. Rotation of the mirror can be achieved either by turning a crank or by operating a connecting rod by means of a pedal. ODOMETER
This machine, known since antiquity, is for measuring distance traversed. Leonardo’s odometer looks like a wheelbarrow provided with sprocket wheels. The vertical wheel takes a step with every turn of the hub of the wheel that rests on the ground. The vertical sprocket wheel has on the inside a peg which, at every full revolution, meshes with the horizontal wheel. The latter is provided with holes through which small metal balls or stones are collected into a dedicated holder. The distance traversed can be easily inferred by counting the balls/stones collected.
PILE DRIVER
A machine of great utility in the piling of hydraulic locks, extensively used already in Leonardo's day. It consists in a vertical frame with a hoist for lifting weights.
He head of the hoist is equipped with a gripping device made of two flexed cross-bows, which are released when the pile reaches the maximum height, thus transmitting to it all the power available. This action could be repeated several times over, until the pile was driven into the ground at the required depth. SELF-MOVING CAR
The numerous sketches and drawings of cars and vehicles scattered throughout the codices testify to how Leonardo was particularly attracted to problems related to locomotion. This model is an example of a self-moving car to which several mechanisms known to and used by Leonardo were applied (leaf springs and geared wheels, in particular). The car was operated through a system implying the hand-loading of the leaf springs; the latter hence transmitted the stored power to the driving wheels by means of a complicated set of gears. The drive was independent on each wheel and was ensured by a wheelwork device which also allowed speed variation. A third wheel was connected to a kind of helm, to direct the car. FAN
This is a curious machine intended for compressing air and force it out of a duct. This device could be used either for keeping the air in a room cool or, more probably, for driving air into a furnace. It is made up of a wooden drum fitted with propulsion fins. It can be either water- or hand-operated. The inside of the drum is divided into four sectors communicating with one another through valved outlets. A certain amount of water is circulated throughout the inside of the drum. The drum, rotating, helps water flow from one sector to the next, thus compressing the air and “forcing” it out of the central shaft which, in turn, is fitted with a valve.