Leonardo da Vinci's water walking shoes

Is there no end to the folly of man? I have been asked to make many things from the sketches of the Florentine master. He has been asked to do many things by his overlords. First, he would turn us into birds and have us fly with wings and gyrating cloth blades. Then he would turn us into fish and have us swim underwater with breathing tubes. Next he would have us crawl about the earth like an armoured turtle. But now I am asked to turn us into ducks so that we may walk upon the water.  

There's not much to go on from the sketch but I have chosen to make shoes and buoyant poles by taking many six-inch pig bladders filled with air and wrapped in leather parcels using thongs and string, and then bound to paddles with leather straps and buckles to hold the whole contraption close to the foot. 

As much as possible I have stayed true to the dimensioning shown in the sketch. By this I am sure to do what is asked of me without daring to change the design of the master. However, while I found that twenty bladders were enough to keep a person afloat they did not allow for the shifting of weight from one foot to the other. In my opinion so many bladders and boards are needed to make this idea work that one would be better to make a small boat… And come out of the effort much dryer!

If I am asked to do anymore of these madcap projects I will hope that I am to turn us into cats. By this we can expect to eat tidbits of fish, and spend our evenings cosily in front of the glowing embers of a fire. 

Leonardo da Vinci's armoured "tank"

Where the Duke of Milan seeks to fly, Cesare Borgia would wage war. 

I was commissioned to make a large scale model of one of the Florentine's war machines. I knew him to be a man of peace, and that he would not eat flesh, but he knew what side his bread was buttered on and kept in good favour by designing weaponry when it was asked for.

The loathsome Salai brought the drawings but I would not pay him the smallest penny to read the jotted notes. This one was easier to comprehend, for Leonardo made use of simple gears that one sees on any building site. I am a cabinet-maker, not a wagon-maker, but I can apply myself to any idea and make good of it. This one seemed simple. It was a little more than a large wooden basin, a kind of low slung barrel, or tank, pierced by four wheels which could be turned by handcrank driving a spoked drum which linked between projecting points from each wheel. As always I made my own drawing to help with my understanding of the parts in the procedures.

At first I was perplexed because the driving force of the gears was such that the two wheels on each side would turn in opposition to each other. 

This detail seems like an error at first and I sketched two other possibilities so the drive of the drums would impel the wheels in the same direction. 

But then I considered that the Florentine master, a man who does not draw details so much is suggest the action of his ideas, is not a man whose perceptions skip a beat. If he drew his gears in such a way then in such a way they were to be. And so I reflected on the requirements of this bizarre vehicle, and thought of the intriguing gears used by Brunelleschi in the building of the Florentine Duomo, and realized that each drum needed to be engaged at different times to achieve its specific purpose. 

So it seemed to me that a man turning the crank, pushing outwards with his weight and pulling upwards and inwards with the force of his legs, would not want to reverse direction to reverse the motion of the vehicle. But by disengaging one wheel and re-engaging its mate then the same circular motion would move the wagon in the opposite direction. Similarly, two drivers could engage the wheels diagonally opposite in such a way that by turning together the whole contraption would rotate on the spot. It was to achieve this that I came up with the idea of a system of removable rods which would pass through a small fixed disk on the driveshaft into the free wheeling driving drum, thus locking the two parts together and extending the force to drive the wheels. Any two wheels appropriately joined by these removable pins would allow the vehicle to go forward, or backwards, or turn. 

Given that this machine of war was a kind of gunship, the intent being to fire cannons in any direction necessary, such manoeuvrability seems paramount, and the engagement of any wheel in order to achieve limitless turning would be the wish of any commander.

My model was not big enough to be anywhere near the size of a real war machine, but it was certainly big enough that I could kneel in it and propel myself across a flat floor.

Once the base was made, and I felt confident in my driving system, the rest was easy enough to fill-in. I had to make the flared skirt around the perimeter, fashion small portals for the cannons, and then provide a kind of roof to offer protection for those inside from any kind of objects hurled or fired by an enemy. 

One can't help but reflect that such a machine as this would instill great fear when first used upon the battlefield. One can imagine a war in which two sides are locked in a sort of stalemate and the one side, in an attempt to break through, comes forth with this amazing contraption firing guns and sowing fear. But yes, it is the way of warfare that after the innovation of one side the other soon follows. And in a short time both sides would be firing at each other from these armoured platforms. Where does the effort end? From each advance comes the new balance of power so neither side can win. Will it always be so with  armies? It is an irony that Leonardo da Vinci, a man of peace, may be a visionary who sees a future where one weapon gives way to another until we have weapons greater than ourselves, perhaps a force of fire so vast it will destroy us all. 

Leonardo da Vinci's aerial screw

Some time ago I received a visit from a servant to the Duke for yet another flying contraption, though this time the model was to portray the idea of a device for a theatre spectacle. Again, within minutes, Salai appeared bearing notebooks under his arm. I had no sooner counted out my Ducats from the Duke than I was reaching into my pockets to pay the rascal for the chance to glean more information from the scribblings of the Florentine master.

As always Leonardo's drawings come with a flair of the artistic. They move off the page, alive and in motion. But I must use my mind to see through the moving parts and capture the static details. I find my confirmation in what small jottings Salai will let me see. From the sketch of the master comes my drawing, thus:

As I see it all moves as one, pivoting on the central column against the stationary slatted base. The base is the platform giving purchase to men who will push the whole in its circular motion by pushing the cross bars, like sailors at a windlass on a ship.

I planned for the model to be 5 feet across. I sketched it out and then set to work with old wood, first making the slatted base, and then the external ring seated beneath it. There are four diagonal support struts and a central column planed down to eight sides. From the column, above the braces, I made square mortices every inch and a half and ran 30 inch rods fanning around for one full circle. At this point I began to reduce their lengths by 2 inches successively until I had completed another half turn.  

The devil in the job was applying the cloth to the framework. The radiating struts support a wire perimeter bound in place by twine. The fabric was applied in sections as large as I could manage to reduce stitching. Even so my fingers became weary plying the thread, and I found myself resorting to a system borrowed from bookbinding using application of glue as often as possible. 

I  also fashioned two little manikins to ride on this merry-go-round as though they were running their little hearts out. I am pleased with them for they have the spirit of da Vinci's drawing. 

As I spin it there's a convincing sense of life, but not even a hint of a downward breath from the swirling sail overhead. I have my doubts that this thing would ever fly in real life. It also strikes me that were it to come off the ground, even for a moment, the slatted base would as willingly spin in the opposite direction to the turn of the upper screw. I think this contraption is better kept for the stage. 

 

Leonardo da Vinci Underwater Apparatus

In these troubled times I keep my head low, but take my orders from whence they come, and am happy to be paid.

Now Cesare Borgia is the man with the orders and the small bag of seven Ducats. Now, instead of a machine that will let us fly I am to contrive a breathing apparatus that will let us swim like a fish. And again, that rascal, Salai, has come with the book of drawings and the price for the time it takes to find the details. And once more the Florentine master is away. I believe they do this to vex me!

The first drawing is little better than a sketch, an idea that more resembles a horse's feed bag and the tentacles of a squid than any design to work from. 

Lost in the margins are some tiny details from which, after yet more coins to Salai, I was able to discern a system of tiny gates to allow a flow of air into the mask through one tube and the expulsion of breath out of the mask through another. 

From this information I was able to make my own sketch and thus get a sense of the requirements to fulfil the obligations of my job. 

At first the task seemed easy enough. I acquired some round discs of glass for the eyes, leather for the job, and from my blacksmith friend the round wire needed to create coils which will line the leather hoses and, in the final use, provide internal support so the hose cannot be crushed by the great weight of water.

Buy my own efforts I was able to turn these coils and create a tapered filler to hold my leather work in place. 

The mask itself was made from a tube of leather onto which I first worked the mouthpiece and the eyeglasses. 

The wire coil was passed through the tube. I hope this is sufficient for I did not endeavoured to sew the leather so tightly to the coil that they cannot be extracted one from the other. 

While this all seemed simple enough I discovered that I was more challenged by the making of the tiny gates fastened to wooden disks. These were secured with thread and beeswax to the wire ring just inside the mouth area. 

The gates were made of leather pieces sewn to a bronze rod which was then fastened by loops to the wood. The attachment allowed for a gentle flap and will, I hope, give sufficient sealing when the inhalation or exhalation of air forces one open and draws the other closed. 

From the outside the mask now looks like this. Tube extensions must be added, sufficient sealing of the seams must be done with some soft beeswax, and prayers must be given for the first person who has to use this!

I  am guessing that the curious sack beneath the mouth piece is to take spittle and leakage from the whole system. Prayers not withstanding, that does not give me hope!

In an attempt to mitigate against leakage I have applied hot bees wax to the joints and seams, and oils and greased the whole. From the upper leather tubing I have added hollow wooden tubes. All is ready for the first mad man who wishes to volunteer. I hope it is Salai, and I hope I have not done my job properly!

Leonardo da Vinci Wing. Fourth Day

I fashioned a fabric wing from one piece of light weight cloth. I sewed the edges with the scallops, as seen in the da Vinci drawing, and used a straight stitch with the ends left loose so that one can pull them to tighten the edges as need be. 

I had to pierce the fabric and reinforce it with more stitching to enable the small levers beneath the wing fingers to be set in place. Then I ran strong and unstretching fishing lines from the levers, through the pulley system, and to the handle. 

There was much fussing and distress while I tied the corners to the ends of the fingers and ran the strings from the driving lever to the projecting attachment  points. The whole contraption was becoming unruly and hard to manage, with a small mishap that caused a fracture in one of the fingers, and which led to much cursing and dismay. But I was able to bind this up with glue and a tight winding. 

The final assembly reminded me rather more of a severed duck's foot than of a wing. The webbed foot will close up if you pull on a tendon. 

I'm afraid to say the wing worked no better for being finished, despite the light weight of the cloth. It was still necessary to work the driving lever so that it raised the wing before it could be brought in a downward flapping motion. The strings worked to some degree of action to close the wing fingers and to catch the air, however the weight of the whole structure made everything tend to sag downward. If I were to imagine stronger spring steel to ensure the fingers remain straight, and if I we're to imagine a counterweight to make the wing point upward before it is driven down, then I would perceive a device so full of counteracting forces that the effort required to make any appreciable movement would require the weight of an elephant. And elephants, I'm sure, will never fly. 

The Florentine is a masterful painter; I have seen his work and it bears a divine 

genius that seems to give solid form to the flat painted canvas. His pen rendition of a flapping wing encourages unquestioning belief, but the reality of his design, as drawn, falls short of its intent in construction. Yet he has these visions that surpass the thoughts of the common man. One has to wonder if, in the future, new materials that are lighter and stronger than any we know today may yet be discovered or devised. New methods of driving force into the working of the wings may indeed bring the power of a herd of elephants into the hands of puny man. And then, yes, elephants may fly. 

Leonardo da Vinci

January 10, 1501

Some time ago I received a visit from a servant to the Duke Ludovico Sforza. He presented me with a small bag of seven ducats and a letter of request stating that I was to build a working model of a devise designed by master Leonardo da Vinci, the Florentine, and that it was to be ready in four days for a presentation at the ducal court. 

Within an hour a servant from Leonardo's workshop arrived with a drawing of a flying wing contraption. With the help of a mirror we read the adjoining text." Is there not more?" I asked. The drawing and text were insufficient I felt. The servant said he would come back with more notes, and I set to work making my own sketches to fully understand the nature and intent of the da Vinci machine. 

I first thought my way through the quick sketch of a single arm. I saw a point of pivot and the leading of a rope. The placement of the pulleys meant that the arm, when moved, would straighten or clench like a waving hand.

But while I could see the down-ward pull of the ropes I wasn't sure how the wooden finger would straighten. 

When the servant returned with a sheaf of papers I reached for them eagerly. He held them back to his chest! "Three Florins", he said.

"You Imp! " I cried, " what of the Duke's order?"

"Yes", he said, " it would be a shame to fail."

I said I would speak with master Leonardo but he told me the master was away in Florence. I asked his name so I could report him for his scurrilous insolence. He said he was know as "Salai". Yes, I thought, a real "devil"

I realized I had no choice so I paid him a few coins and in an hour and was able to peruse the mirror text. I was able to glean enough of the information I needed and could then dismiss him with a box to the ears for his insolence. I then put myself to the second drawing. 

I knew I  had enough old wood for the job but went at once to my friend Stefano, the blacksmith, for necessary spring steel and ring bolts, and to my brother Andreo, the sailmaker, for cloth and cordage. By the end of the first day I had amassed all my materials. 

Right now had only three days to complete the model. By the Duke's instructions I knew that this model was to be true to Leonardo's drawings but that my job was to reveal only design issues that needed correction, and that I was not to attempt my own innovations. 

That was a small relief. 

ON THE SECOND DAY my goal was to complete the structure of the "bones" for the working wing. I spent the morning making the central finger and connecting it to the horizontal member which I turned on a lathe. This served as an axle with two extending fingers to help spread the wing. The work with the wood was easy, for that is my trade, but manipulating the spring steel and making the joint work was harder. In the end, however, I was able to get both sufficient spring and flexible stiffness in the joint by using some leather members on either side and, ultimately, stitching a sheath of leather over the whole joint. 

With this one component made it was quick and easy to follow up with four other fingers angled into the main axle so they would fan out, and then to add two static rods as a last way of spreading the final fabric. 

MY TASK ON THE THIRD DAY was to fashion the bearing arms for the wing, to join the wing to the driving lever with two inter-locked steel rings, and to make the structure through which the driving lever could operate. Again, these tasks were easily accomplished with the help of good augers, and sharp chisels and saws, so as to create the necessary mortises and tenons. My friend Stefano also came through with the last elements required, namely the two inter-locking rings and some good steel spikes. 

I mounted this all on a solid base ready for the first trial, and was proud of myself for realizing that the one driving lever would have to be without a point of pivot to ensure that the thrusting aspect of the system would not cause the levers to bind and be locked in place. 

In my first fledgling attempt at working the wing I was shocked to realize that the downward thrust, as implied by da Vinci's drawing, was an impossibility. 

The sheer weight of the wing structure itself made the wing fall downward. I had to apply considerable force and directional manipulation in order to raise the wing and resist its wish to fall. 

At first I was aghast and felt the sweat of fear that I had failed in my job. But then I realized my job was simply to represent the drawings of the great Florentine and, to my best ability, to neither add not take away any element but that which was clearly illustrated (or not). Indeed, with great relief I realized that the Duke's commission was as much to prove that the idea of the wing would fail as that it could be a success. With this thought in mind I went to sleep, with a light heart, knowing that I still had time in hand to complete the fabric wing and to lead the various strings that were part of the flapping mechanism. This would be my task in the final day still to come.