Friday, December 21, 2007

The windbüchse of Prostl - Part 6
A fictional account of the development of an early airgun

by Tom Gaylord

Part 1
Part 2
Part 3
Part 4
Part 5

The opportunity came within the next week. He called at the great hall and found the nobleman between work, so the two men retired to the inner garden where they could be alone. He presented the younger man with a dark walnut case in which there were divided compartments for each piece, much as a fine firearm is housed. There was the butt in one section; the barrel and lock in another—the longest, which ran the full length of the case; the condensing syringe and a separate set of handles with which to pump it; a ball mold; a set of spare horn seals for replacement when the gun started to loose force; an oil bottle for lubrication of the seal between the butt and lock; and one more section. The final section was covered, and contained balls already cast, plus the small key to lock the case. The entire presentation was as breathtaking as the very idea of the gun, itself.

The baron found himself without words to express his gratitude. This was so far beyond his expectations that it was almost something else, indeed! Oh, how he would lord it over his cousin when next they met!

Then, he chanced to notice the number three impressed on top of the lock. "Herr Bidderman, what does this number signify?"

"My lord, you were so concerned that the Emperor would try to steal this gun from you if ever he learned of its existence that I devised a way to prevent that from happening. I put the number three on the lock because I am going to make two more guns especially for the Emperor. They will be a matched pair of the most exquisite beauty anyone has ever seen. No one will have a pair of guns, wind or firelock, that compare to what I will make for him. And, they will be the last Royal commission I ever undertake."

"I am astounded, my old friend. What gave you such an idea?"

"My lord, I know that my time on earth will soon come to an end. I have no apprentice to whom I can pass even a fraction of the secrets I possess, so they will perish with me. If I were to die with a such speculative commission in progress…"

"The Emperor will break down the gates of heaven and hell to find a craftsman to finish the project! He will build his own guns and leave mine alone! By Jove—what a plan!"

"Yes, my lord, I think I out-foxed him this time."

True to his premonition, August Bidderman closed his eyes for the final time four months later. He died in his sleep, apparently without a struggle of any kind. The baron laid him to rest in his family's own plot in the yard of the chapel that served the north end of the valley. The entire village of Prostl turned out for the funeral, and there wasn't a dry eye present.

The Emperor never did learn of the existence of Von Eiger's fabulous wind gun, but the cousin from the Low Countries certainly did! He was consumed with jealousy after shooting the piece one afternoon, so Von Eiger had to let him take it back to Antwerp to have it copied.

There wasn't a craftsman willing to undertake the work in Antwerp, but in the city of Liege there was a man who said he could do it. He kept the gun for almost a full year before returning it to the cousin, who raced across Europe to return it to the baron—so long had it been out of his sight.

The copy proved to work as well as the original, so the workman in Liege began making more of them for his other patrons. Soon, other men in town copied the design, and they began turning up everywhere. Several centuries later, there would be such a proliferation of the pattern that some experts would come to believe that it had originated in Liege.

The baron's gun was handed down for two more generations, until the dissolution of the family estate in 1796, when it was sold at auction to a wealthy merchant from Ingolstadt. He kept it for 20 more years before selling it to cover a loss in his business. The gun's whereabouts were lost from that time until the end of World War I, when it was rediscovered in the ruins of an estate in western France. The liberator, an English officer, took it home with him as a souvenir, but to keep curious eyes from discerning its presence during transit, he left the case where he found it.
His family later sold the gun at a weapons fair in Birmingham, in 1956. Then, in 1968, the gun was documented in a short article in a British airgun magazine. This brought it to the attention of a wealthy American collector who flew to England and bought it from the owner.

In 1989, the gun was again sold at a gun show in Dallas, Texas. By that time, there was only the gun. All the other accessories, including the pump, had been stripped away by the indifference of casual owners over the centuries. It still fetched $8,500 because of its great elegance and beauty. The sights, which the maker believed to be made from elephant tusks, were actually discovered to be mammoth ivory—obtained from frozen carcasses recovered by Russian expeditions in the 18th century. They survive to the present day.

Today, the outside lock air gun made by August Bidderman for Baron Von Eiger resides in a collection in the United States. Although the story of the piece sounds complete, its history is still unfolding. The great care with which it was constructed has given the airgun a kind of near immortality. Anyone who possesses it for a time will do his utmost to conserve it.

The valve seals have been replaced with modern components, which, while they give no more power, at least seal it so that sperm whale oil is no longer required.

August Bidderman died in the year 1727, but his masterpieces still live on. The one and only wind gun he ever made is perhaps the final epitaph for the man whose name has been all but erased from the pages of history. A work of art that inspires all who see it to preserve the most tangible part that remains of the old master.

Sunday, December 09, 2007

The windbüchse of Prostl - Part 5
A fictional account of the development of an early airgun

by Tom Gaylord

Part 1
Part 2
Part 3
Part 4

Could a spring be larger than the lock it powers? Why not, he wondered? Why not reverse the working of the entire lock and put all the springs and levers on the outside where they could be as big as they needed to be? It would be like the sawmill that had so captivated him. Instantly, much of his already fabricated lock dissolved in front of his eyes and re-formed in a simpler yet far more elegant fashion. An outside lock! It might work at that!

Most of the work he had done on the lock to this point would be undone by this change, but the new idea was worth far more than the extra effort it took to accomplish. Only the heart of the lock, the essence of its operation, would remain, but with this new revelation, Bidderman finally knew he could make the gun exactly as he had imagined it many months earlier. Simply turning the lock inside-out made everything possible. He set to work at once.

He used the last of his precious steel for the new parts. The other parts for the first lock which were now unused would supply him with more than what he needed to finish the job. The hammer spring was fashioned from an immensely thick bar of steel, but this time he didn’t fold the metal with the craft he had learned from the Spaniards. While Damascus steel is strong, it doesn’t have the resiliency of a homogeneous steel bar, so the spring had to be made of a single unfolded piece.

And August knew a thing or two himself, so even here he improvised in ways no gunsmith had ever dreamed. Instead of just attaching his spring to the hammer in the usual fashion, he rigged a unique arrangement of force multiplication, by adjusting the geometry of the main spring on the hammer as it traveled through its arc. At the start of its journey, when he wanted to generate the greatest force, he made the spring be its strongest, with compound angles only the finest craftsman would be astute enough to ascertain. Power was provided not only by the conventional V at the apex of the triangular spring, but also by the lower arm into which Bidderman forged a slight arch. When the two arms came together, he could get still more power from the lower arm, by making it flex against the upper arm in the manner of a flat spring. In effect, he had combined the power of two springs into one! But that wasn't all.

The end of the spring that bore against the hammer was not attached to it directly. Instead, it slid along an inclined shelf at the bottom of the hammer as it moved through its arc. The point of contact was at a variable, increasing distance from the fulcrum, so, as the force gradually lessened from the expansion of the spring, the mechanical advantage became ever greater. That, coupled with the inertia of both the moving hammer and the valve lever, kept the force driving the connecting rod constant. The effect was one of continuous force, rather than the simple banging of a heavy weight against a valve stem in one uncontrolled punch, and it was the essential thing that differentiated Bidderman's lock from any other. Centuries later, only a few makers would be able to discern the mastery of design that went into it.

The butt and valve could remain as they were. The outside lock pattern had no real impact on them, other than to reverse the direction of the valve lever, which now had to pass through the lock body, itself. He worked for three weeks making the special tools required to cut a perfectly square channel, yet having the same curve as the lock body. Through this channel passed the square-sectioned rod that connected the valve lever to the valve. The rod had to be fitted tightly to the channel or else the wind would escape that way and fail to act on the ball in the breech. It was a most complex cut to make—one that tested the skill of even the master. Until this point he imagined that music boxes were the most complex devices he had ever worked upon, but this single rod made him change his opinion in favor of the wind gun. A perfectly square channel cut on a curve. Was there ever a thing harder to do? If there was, he fervently hoped he might never encounter it.

With all his work keeping him long hours at the bench, old Bidderman took sick and was abed for several weeks. The neighbor wife who looked in on him from time to time now came by twice a day with food and to check on his condition. When the Baron learned of his illness, he sent his personal physician over to attend the old man, but, alas, the news was not good. Bidderman had the coughing sickness that usually meant the end of life for one as old and frail as he.

The Baron himself came round to see his faithful servant and was distressed to see that his physician had told the truth. The old man was dying, and from the look of him it wouldn't be too long in coming. He dispatched three of his servants to attend to the old man night and day, to make sure that he did nothing but lie in bed and try to fight the cough that racked his body.

For three weeks everything in the village was suspended as the life of August Bidderman played out in his humble cottage. But finally there dawned a day when he was well enough to be up and about. That day signaled the start of his long recovery to such health as he could be expected to attain with the coughing sickness.

Two weeks after getting up from his bed, old August worked in his shop for a short period. He was as fearful of his frailty as anyone, so he didn't try to push himself. Slowly, he worked himself back to a pace that was, if reduced from before, still a full day for any other man.

The components of the valve and butt were joined by brazing-in the threaded connection, which provided a place for the joining of the butt to the lock. The valve was screwed into the butt threads provided in this joint.

The barrel was threaded on the other end of the lock and the new gun was nearly complete. Sights were fashioned for both front and rear, as this was a rifle and not a smoothbore. For both sights, Bidderman used a material which looked like modern African ivory, but was actually much older. It had been obtained from the tusks of long-dead elephants found frozen in the eastern lands. He purchased a thick wedge of the yellowing material in a specialty shop in Vienna, along with some special figured wood he needed for music boxes.

The trigger was the finest feature of all. It curved backward and down, so that the tip was exactly in the middle of the piece. Like the powerful crossbows in the royal armory, this gun could be fired easily by a person holding it on either shoulder. As his patron favored the use of his sinister hand, this ensured he could use the piece as easily as the maker or anyone else, for that matter.

When all was done on the rifle, August Bidderman quickly fashioned a condensing syringe from the notes he had gathered while still in possession of the first wind gun. He made his pump a little longer and thinner, to make the effort less, and he lapped in the head of the piston with the dust of fine casting sand, which was the finest scouring material known to exist. When he was finished, the pump rod operated without a sound and could be stopped cold by holding one's thumb over the air hole.

Finally came the moment he had been waiting for. It was time to shoot the gun. From a mold he made, he had cast some lead balls which fit the bore perfectly when patched in the Dutch style with a linen patch soaked in sperm oil. Then he withdrew the hammer until the trigger caught it. Taking aim at the wall opposite his bench, a length of seven long strides, he shot at a knot in the wood. The gun roared, but not as much as he remembered the first one doing. The ball struck the knot on one side, so he corrected the rear sight leaf a small amount and fired a second shot. Two things now surprised him: one—the gun shot as strong as at first, and two—the ball struck close to the center of the knot.

Since this was a test of the gun, August reloaded and shot a third time. Amazingly, that shot was just as powerful as numbers one and two, and the strike of the ball blew the knot clear out of the plank.

In all, there proved to be four shots that had good force in that rifle, before the butt had to be removed and filled with more wind. Four shots! And each was powered by a substance so ethereal as to be invisible. Old Bidderman was pleased beyond his wildest hopes, and he knew his noble patron would be pleased, as well. No wind gun had ever performed as well as this one, which made the appearance of the mechanism outside the lock all the more bearable. In fact, he thought, it was very pleasant to see the workings of a machine that could produce results as dramatic as these. He couldn't wait to see the Baron's reaction to the piece when he presented him with it.

Monday, December 03, 2007

The windbüchse of Prostl - Part 4
A fictional account of the development of an early airgun

by Tom Gaylord

Part 1
Part 2
Part 3

The butt of the piece was intended to hold the condensed wind, and must therefore allow none of it to escape. He fashioned it from thick sheet iron, which he folded into a long hollow triangular shape that was locked together at the seam on the bottom with a special mechanical lip and shelf. The butt plate was similarly attached, then brazed with hot brass around its seam to prevent leaks. After two dozen iron rivets had been installed to prevent the long seam on the bottom of the butt from weakening under pressure, it was similarly brazed for integrity. It took no small skill to braze that long seam accurately, but such skill was part of what made the old man the master he was. Now fashioned, the butt was ready to contain the real secret of the gun. Bidderman's special wind-lock valve.

In his dreams about the gun, the master had seen that wind, like all natural forces, moves according to rules that never change. Once, when shooting the prototype gun from the Low Countries, he had chanced a second shot and found it to be nearly as strong as the first. That started him thinking that if the wind was allowed to exit the gun through a portal that remained open for only an incredibly short amount of time, there might be enough remaining in the butt for a second shot. Perhaps even more. He began to think of the wind as he did the water that powered the village mill. It was controlled by the width of the millrace and therefore was always moving the mill wheel with the same force, regardless of how high the stream was.

From his clockmaking, old August knew that force was the result of both opportunity and desire. The wind in the butt had a great desire to escape, but it didn't have the opportunity until the valve provided it. By allowing only a small opening to pass the escape hole for a brief moment in time, he could control how much wind was expelled with each shot, thereby leaving some for the next shot.

He made many of the valve parts from brass, for he knew that metal best of all. It would work tirelessly for years without lubrication. It could work at great pressure, so it was perfect for a part that would reside in the butt, where the pressure would sometimes be extreme. But best of all, brass would not corrode like iron and even steel. This was important for a part subjected to the heating of the condensing syringe and the cooling caused by sudden release at firing. Yes, brass was perfect for this job.

To seal the opening at the tip of the valve, he selected material from the fresh horn of a bull. When cut to size and fitted to the steel rod that passed through the brass valve head, a ring made from bull-horn stopped the flow of air almost perfectly. But almost was not good enough for August Bidderman. He desired a vessel which, when filled with condensed wind, would retain all of it for a full day or even longer. So he turned the steel rod tipped with bull-horn against the brass end of the valve, adding common chalk for lubrication, until the valve screeched like a vixen in the spring. This was the sound that announced a perfect mating of horn to metal. When oiled with a small amount of sperm oil, the valve would contain the wind tightly. Bidderman pronounced the work good, but he did one more thing before moving on.

He removed the brass valve from the iron butt and smeared grease on the walls inside the butt. Now, when dirt particles made their way into the butt from the condensing syringe, they would stick to the grease instead of getting into the smooth valve parts to disrupt the seal. The gun from the Low Countries had been treated in this way, and he could see the value when he examined it. Before returning that piece, he had cleaned out the old grease and applied fresh in its place. Such a job might be expected to last for up to five years, depending on the goodness of the grease, how many times the butt was filled and how quickly the grease aged. Except for a covering, the butt was now complete.

The cover was fashioned from the skin of a shark! Bidderman cut the leather to fit, then artfully stitched the seam with the finest deer tendon fiber. Then he slid the covering on the butt and immersed it in water for a day. When it was removed and dried in the sun, it tightened like any leather would, adding strength to the butt. This material, known as shagreen, was not common in Bidderman’s day, but it would become the most popular kind of covering for wind gun reservoirs within the next 50 years.

For the lock and all its working parts, only forge-hammered steel would do. Bidderman carefully heated each part of his lock in the forge then skillfully hammered them into the proper shapes. Files did the finish work, of course, but he wanted to get as close as possible with the forged part to retain the integrity of the metal's own living grain.

One part that almost stumped the old master was the powerful spring to drive the hammer. An ordinary snaphance or flintlock hammer simply causes flint to strike steel with force, but Bidderman's lock required the hammer to push the valve lever through a determined arc against the force of wind trying to escape the butt. That was how the marvelous valve he designed worked. It had to be pushed both open and then be allowed to close by the two-way action of the lever, which was made to operate by the unique shape of the hammer.

To do all that work required a spring that had never before been constructed. Oh, far larger and more powerful springs existed for a long time before this. Coaches had them, as did a number of large mechanical devices. Even large clocks had them. But never before had the power required for Bidderman's lock been made into a spring small enough to fit within the lock he designed. He had to experiment until he got what he wanted.

Weeks went by as the old master labored to fashion that which he had never seen. A few times he lost confidence and had to do other work until his mind had cleared once more. One full year and a part of the next had passed since the Baron had given his word to proceed and still the promised gun did not exist. And, unless he could fashion a spring to power it, it never would.

He tried new shapes and sizes but nothing was to any practical avail. The closest he got was a huge spring that was too outsized for any gun. By tying his gun to the workbench and leaving the lockplate off, he could mount this spring and get off a shot of wind from the butt before the spring jumped out of position.

What he needed was a spring with the strength of this huge one, yet its size had to be more like that of a firelock spring. He made one that was so thick it stuck out to the side of the lock, but it did remain on when he shot the gun and the whole thing did work. But this fat spring was too ungainly for him to put on anything that bore his own precious name, so back he went to figure something new.

All this power was causing the outside of his comely lock to triple in size. No longer was its elegance visible behind the huge outer housing needed to contain both the huge hammer spring and the trigger spring.

He needed the mass of a large spring to fit into the space of a small one. One day, for no reason he could discern, he remembered his youth as an apprentice sawyer, before he had impressed the father of his current patron with his great talents for metal work. As a young apprentice, he was the one who got all the worst work, so of course he was the man down in the pit who pulled on the bottom of the saw.

The pit man had the dirtiest job at the mill, for the sawdust fell straight down on him with every downward stroke of the blade. There was no breeze in the musty pit, so in minutes, he was covered with sawdust from head to toe. Even though he took three dunkings a day in the stream, he still had sawdust in every crevasse of his body. It was why, to this day, old August would only used riven planks to make anything. It was his contribution to the pit men of the world, to keep the demand for sawn planks to a minimum.

For several years, though, he had been aware of a new machine that eliminated the man in the pits, by allowing the top man to do all the work by himself. Because of his experience as a youth, he paid keen attention to how that machine was constructed, since it paroled so many young men from a purgatory of filth and bad health. The interesting thing about that machine is that it multiplied the force of the one sawyer by extending his arms through levers. An especially long lever of iron, called a pitman arm, did the work that a man formerly had to do. The pitman arm was attached to a powerful spring, and since the entire mechanism was too ungainly to fit into the pit, it was constructed in such a way as to remain outside. The machine was therefore much larger than the workplace, and had to be built outside it. Could the same be done for the spring of his lock?