Grantville Gazette, Volume 7
"I think so," Dury said, "although that might limit the number of copies that he decides to make. Don't you want any money for this?"
Colette shook her head. "No, my purpose is to disseminate the knowledge as widely as possible, not to restrict it. And I am just the synthesizer. Most of this knowledge is easy to come by here in Grantville, if you know where to look."
Dury smiled. "Well then, since I am headed to England tomorrow, perhaps I can place some copies in the right hands. How many do you have?"
"Three plus the original." Colette reached into her desk and pulled out three large envelopes and handed them to Dury. "One is for Samuel Hartlib, one is to be mailed to Nicolas Peiresc, and the third to Marin Mersenne." Colette smiled. "I believe you know those gentlemen?"
Dury gave a start of surprise. "How did you . . ."
Colette grinned. "I was told that a messenger would come, John." She looked up at the ceiling and then back at Dury.
Dury understood immediately. "Mysterious are the ways of God, Colette. Mysterious, indeed."
Before he left, Colette Modi made him promise one thing. "Initially I want no one to know that I wrote these, John. So please promise me that only the name Crucibellus will be connected with these manuscripts. The address I have left in the manuscript is Inn of The Maddened Queen. That way many will assume it is simply a postal drop."
Dury smiled. "I promise."
Two months later John Dury was in London. It was there that he mailed a copy of Colette's manuscript to Marin Mersenne in Paris and Nicolas Peiresc in Aix-en-Provence. The third he took to Samuel Hartlib.
* * *
To say that the Crucibellus Manuscripts took the European mathematical community by storm would be a vast understatement. In early 1632 many Europeans were still unaware that something unusual had happened to their universe. Even those who had heard the tales of a community of Englishmen in Thuringia tended to discredit the idea unless they had actually traveled to Grantville themselves. But when the Crucibellus Manuscripts began circulating in 1632, people's minds began to change. It was not that all of the concepts were totally new and different. But it was the style and the breadth and the mystery which set intellectual circles abuzz. For Crucibellus had outlined the topics of future manuscripts and promised that each would appear at approximately three month intervals. Mathematical Symbology of the Future. Analytical Geometry. Differential Calculus. Integral Calculus. Differential Equations. Matrix Algebra. Probability. Statistics. Fractals. Special and General Relativity. Quantum Mechanics.
The style was often brutally terse. While only the most essential concepts were given, the example problems in the manuscripts were explained in clear and exquisite detail and were often taken from problems the reader could imagine from everyday life.
And then there were the challenge problems. Theorems unheard of. Problems never dreamt of. Problems no mathematician in the seventeenth century could solve, especially in the ninety days before the answer would appear in the next manuscript. The first challenge problem set the stage for the rest: Prove the existence of the Euler Line. That is, that the orthocenter, centroid, and circumcenter of any triangle must lie in a straight line, with the centroid exactly twice as far from the orthocenter as from the circumcenter.
Soon, of course, a number of mathematicians had discovered the real name of the author and were studying in Grantville themselves.
But without the Crucibellus Manuscripts it might have taken years to stir their curiosity.
Ask a mathematician three hundred years later who Mike Stearns was and many would give you a blank look. But ask them about the Crucibellus Manuscripts and watch their eyes light up with recognition or listen to them discourse for hours on their impact.
The Crucibellus Manuscripts.
Long will they echo across the corridors of time.
NON-FICTION
The Mechanical Reproduction Of Sound: Developing A Recorded Music Distribution Industry
By Chris Penycate and Rick Boatright
Part 1. Preparing pre-recorded material for distribution
Sound, no matter how complex, is just waves like the ripples in a pond. It can be considered as the displacement of molecules from their place of rest. A more technical definition would be: Sound is a series of compression and rarefaction waves in a substance, solid, liquid or generally in our experience, gas. Our aim in recording is to precisely reproduce these waves in another place and/or at a different time. As exact, absolutely precise reproduction can't be done even today, we must be satisfied with successive approximations and keep aiming to improve. A cheap, bad telephone will make something that sounds "sort of" like you. A mechanical phonograph will sound "better" but still not exactly the same as you. We can successively improve our approximations until, with modern speakers, decent amps and CD quality recording it would be very difficult to tell which was "real" you or the recording. But you might still be able to tell that there was a difference.
First exercise for students—take an inflated balloon, hold it in front of your face, and sing at it. You can feel the vibrations through your fingertips (and in good lighting, by singing loudly, watch them travel over the surface). As the sound hit's the balloon it wiggles, which is about how the ear drum works. If we were able to attach a needle to our balloon with glue or tape, we could have made it inscribe a wiggly line on a soot-covered piece of paper, which shows that we can make a record of the sound. This would demonstrate that enough energy is being transferred to do mechanical work.
How to turn Wiggles on a Disk into Sound
Air seems very easy to move, but trying to move it fast requires energy—as any manufacturer of sports cars could tell you. They call it air resistance, we call it acoustic impedance, but it comes down to the same thing. Despite what residents of Florida might believe, air prefers staying in the same place to chasing around. In the above drawing, our needle wiggling along the groove will move a tiny bit of air in contact with it, but that moving air doesn't have enough energy, enough "oomph," to make sound that can be heard throughout the room. If we hook the needle up to a lever, and use the lever to wiggle a thin diaphragm (like a drum head) back and forth, then the diaphragm moving back and forth moves more air, which then has more energy, (more oomph) and can be heard more clearly. This uses more energy. We need to push the needle back and forth harder against the grooves. Pressing harder means that there is more friction. That causes more wear on the record, but we get a louder sound. This is a good thing. But we can't keep making the lever longer and longer, making the diaphragm bigger and bigger, because eventually, we would just snap the needle off. Needles aren't infinitely strong. There has to be another way to turn the small weak wiggles of the needle into a loud sound that can fill a room. To do this, we can use a bit of physics in the form of a horn.
Those big flower shaped horns on old crank up record players weren't just decorative. They were very important to hearing the music. Without the horn, you have to put your ear right up against the diaphragm as though you were listening to a telephone. The horn is critical. A horn works as an acoustic impedance converter. It converts high velocity, low-pressure waves at the wide end into low velocity high-pressure waves at the small end. Or vice-versa, it converts low velocity, high-pressure waves at the small end into high velocity, low pressure waves at the wide end. Look at the diagram. We have a little needle wiggling back and forth, getting some energy from the turning of the record player; (we're literally moving the needle back and forth with the energy from the turning of the record. That is what powers the wiggling.) So, our needle wiggles back and forth, and moves the lever, and the lever wiggles the diaphragm. So far, so good. But the diaphragm moves back and forth fast, literally hundreds to thousands of times a second. (The "A" above middle "C" on the piano requires the needle to wiggle 440 times a second.) So, the air right beside the diaphragm is nearly being torn apart. The pressure spikes up fast, and then, as the diaphragm moves back the other way spikes back down fast.
So, you have very high pressures right next to the diaphragm. Now. If we put a properly shaped horn next to it, the horn can take this signal and "spread it out."
If you're a physics geek, the horn acts as an impedance transformer. If you're a poet, the horn takes the thin, reedy sound at the diaphragm and makes it "bigger." This is exactly the same sort of thing that happens in a trumpet or a saxophone. The trumpeter's lips going bzzzzzz make a thin, reedy sound that has no carrying power. The "trumpet shaped" trumpet takes those sound waves and transforms them into Louis Armstrong's powerful music. The sound horn on a record player does the exact same thing. The horn on the record player modifies the output of the diaphragm, making it more listenable.
It has long been known that a trumpet could annoy people a lot further away than a flute. The first record players, (phonographs) used horns that were like cheerleaders megaphones. They were small simple cones. They were adequate for speech, but didn't reproduce highs or lows well. The people building phonographs pretty quickly changed the horn shape. They settled on what turns out to be the theoretically perfect shape - that big-belled flower you've seen in pictures. It's called an "exponential horn." The Grantville developers don't need to know why this shape is best, they can merely copy an existing design, which had been polished by previous trial and error.
We can use the same horn, diaphragm and needle to CUT records if we want to. Attaching a diaphragm across the narrow end of a horn concentrates the sound energy and allows the needle to cut the wiggly line into a piece of wax—or, as in the original, a piece of tin foil wound round a drum (Please look up Edison, Phonograph on the web). So, at this point in our development of a recorder, we're up to where Edison was in his patent. We have a line on a soft surface which exactly follows the movement of the diaphragm (and slightly less exactly the variations of air pressure at the diaphragm, and even less exactly the variations in the room, but it's a start. We can do intelligible speech already).
If we reposition the system and drag the needle back across this groove we'll get a sound at the mouth of the horn which sounds at least a little bit like the original. The problem is, as we do that, it destroys the recording we made. That's not exactly what we're looking for.
If we use a lighter needle/diaphragm assembly, we get a sound much more like the original, and we will be able to play our recording several times before our master wears out. Still, we would like to be able to play a recording many times. We would also like to make many copies of a recording. Even so, the principle of the recording system is simple. We take something soft moving at a constant speed past a needle which is vibrated by the energy from the air. If this something soft hardens with time (like cheese or play-doh) or with varying temperature, or can be treated to harden chemically, or can take a hard, regular surface coating, we have the basis for a permanent medium. Simply dragging a long candle past the diaphragm won't work, however. For two minutes of sound, linear motion requires about fifty meters of candle. Storing and carrying them would be inconvenient. The solution was to coil the recording up some way. Two techniques were tried.
First: Edison's solution: Spin a cylinder and wrap your groove around it like thread on a spool. If you build a drum that you can slide thin cylinders onto, you can "change the records." This has the distinct advantage that the speed of the groove past the needle is constant. It has the disadvantage that making the recording play longer takes more and more "tube." An Edison tube "LP" would be six or more feet long.
Second: The Victrola solution. Use a flat disc (a 'record'). The groove coils from the outside in towards the center. Unfortunately, since the disk turns at a constant angular velocity, when the needle is in the groove near the outside edge, the speed of the groove past the needle is much higher than the speed near the center of the disk. More about that later.
In both cases the play head was moved by the groove itself. Disks became the de facto standard, in the OTL for two simple reasons. They stack better. Tubes have all that annoying space in the middle of them. And they are more copyable. (More on that later.)
Problems remained. The signal had to be fairly loud at the cutting head for anything to record at all (Bessie Smith powering away at the blues in front of a big band gave acoustic levels which are hard to believe in this age of universal amplification) and as to subtle, delicate performances, you can forget about them. Before amplifiers came to be, recording engineers had to constantly balance opposing desires.
On the one hand, they wanted the recording media to have good mechanical stability. A stiff material could accurately record subtle details of the sound. On the other hand, they wanted the recording media to be soft and malleable. Softer material could record weaker, softer sounds.
Similarly, the engineers were torn between higher rotational speeds, which allowed more accurate recording, especially of high pitched sounds, and lower rotational speeds to extend playing time. Placing the grooves closer together also extended playing time, however, wider groove spacing allowed bigger wiggles to be recorded, and thus, louder sounds. Larger discs extended playing time, but increased storage and transport difficulties. It was in everyone's interests to have a standard. The standard that was settled on was ten to twelve inch disks spinning at 78 RPM. A lot of interesting (loud) music was recorded like this.
Let's return to the advantages of disks. If you record on tubes, they are very hard to copy. Each tube has to be recorded individually. Bessie Smith had to belt out another one for every record sold. Good for Bessie, regular employment. Actually, not that good for Bessie. It was a boring, hard, low-paying job. (Of course, in the New Time Line, we won't be recording Bessie directly, we'll be recording a recording of Bessie. Still, it's not the best alternative.)
On the other hand, disks can be "pressed." When the recording process was finished, the master was cleaned of any small bits left over from the cutting process, coated with graphite, and plated with metal. This gave a negative of the original which could be used to produce multiple copies. In the case of popular artists, the process could be duplicated again and again. That way you could have sub-masters and archive masters. This was necessary since the masters could only be used a certain number of times.
Record players in houses had steel needles or blackthorn thorns attached to a diaphragm. The diaphragm was located in a cavity leading to a horn. The narrow part of the horn was hinged so that the playback needle could track the groove, or be lifted off and folded back to change the disc. The horn was made as large as practical. It was often built into a large cabinet like a sideboard or hutch, coiled back on itself and filled the furniture. The larger the horn, and the slower its flare rate, the better the bass response. Just like up time, speakers with big booming bass have to be large. The same is true of horns in mechanical players.
It is important that the speed be constant or the music goes Wow-wow-wow. This is considered bad. Constant speed was controlled by a centrifugal rotating watsit. The watsit reduced power when the arms swung out to a predetermined point. It's probably easier to copy the speed governor in an existing mechanical phonograph than to reinvent it. It is far less complicated than a watch. Many of these mechanical record players were still in use in the 1950s, half a century after the invention of the vacuum tube. Victrola's may not produce the great sound of modern CDs, but people were happy with the results and could listen to their favorite artists at home without paying a months salary to go to a concert (assuming there was a concert on) Still, one couldn't say that the illusion of "being there" was excessive.
At the beginning of the twentieth century came the next major development—the thermionic valve, or vacuum tube. 1907 saw the triode, and gave us electronics. Electronics was important, even if the players were still mechanical. Recording engineers could now start building decent microphones and amplifying them up to reasonable levels. They were now able to amplify quieter music and cut records electrically. Early electrical cutting heads look a lot like the old mechanical ones (with the horn removed
, of course) but the diaphragm is made of iron, moved by an electromagnet which is driven by an amplifier.
As the engineers started to use electronic recording heads, they noticed a that the electricity flowing through the head caused it (and the needle) to get warm. The engineers kept increasing the electric power to the head so that they could increase the amount of back-and-forth wiggle. This let them cause the cutting needle to more and more accurately follow the real sound waves in the air. The more power they had, the less the stiffness of the medium mattered. They could force that little needle to wiggle the way they wanted.
The more power they put in, the hotter the needle got. Hot cutting heads became common. This turned out to be a good thing. The hot needle softened the recording substrate, and made it easier to cut the record exactly the way they wanted. After the hot needle passes the disk cools and hardens again. Of course, if the cutting head gets too hot, it melts the solder and the disk under it, so high power cutting heads have to be cooled with pipes of water or oil.
There are two advantages to the hot cutting head. One: the records sound better because they more accurately track the sound from the microphone. Two: we can use harder cutting blanks. With harder cutting blanks it becomes possible to play our cuttings (not too many times) and check that what we recorded is what we wanted.