The
History of This Website
lemmatalogic.com
is a placeholder website for add-on domains. I used it as a simple linear document
with subjects related to science and technology. I removed most of the
content but left some, especially the article about Heaviside, all below the
Glassblowing text.
I really do not want to convince anyone of
anything. But some may find some of the information useful. If so, enjoy.
Glassblowing
So, apart
from science, technology and inventing, one of my activities is glassblowing
in a hotshop. I learned the very basic of
glassblowing at the Morris County School of
Glass several years ago. I took several 6 week
courses and had some excellent instructors, of whom Hannah Muller stood out.
I met my benchmate Charlie there, who is as
obsessed with glassblowing as I am.
We moved our activities to Glassroots
in Newark. The hotshop there is managed by the very
gifted lead glassblower Jason Minami. He is a glassblower who has an uncanny
connection with hot glass. He understands hot glass and makes it do, or
rather guides it to do, what he wants to achieve. For anyone who tried
glassblowing, it often seems that hot glass has a mind of its own and
actually fights the artist.
Here I am in the Glassroots hotshop, working on a bottle shape, preparing to transfer
to a punty.
I have done this now for about 5 years and finally,
mainly under the guidance of Jason and my continued collaboration with
Charlie, who is a daring experimenter, start to get somewhat of a grip on
some of the techniques.
The reason to write about it is not because I have
reached expertise. Not by a mile. But I am obsessed with ringed blown glass
and after many, many failures it seems I am making some progress. I will keep
this as a record of what I try, what seems to work and what fails and why.
Two of my favorite object shapes are bowls and bottles,
which both have their idiosyncrasies in the creation process. Early in my
glassblowing efforts I came across the two excellent videos by Powell Scott
in making ringed bowls.
Here is a blown bottle on the pipe, ready for transfer. I
had to do many, many trials before finally somewhat mastering this seemingly simple
but beautiful shape.
No Good
Glass Ring Molds
Creating colored rings in a blown glass object can be
done in at least two ways: You apply the colored rings on a bubble or parison
or the rings are already part of the set-up. Applying colored rings by
rotating colored glass off from a punty on a
parison on a pipe is certainly possible, but extremely difficult to get an “incalmo” effect. I have tried it several times and found
the technique interesting but difficult with not the desired effect.
Creating an “embedded” rings piece requires, well, glass
rings. Preferably all of the same diameter and different colors. When stacked
in a cylinder, and having all rings tack-fused to each other, you have the
basic set-up for a blown ringed piece.
This is the, for me, stunning thing. While we have a
technical solution for almost anything, there are literally NO MOLDS to fuse
frit (or ground glass) into a ring. Especially for rings that are required
for the ringed bowl, which would be a ring of about 2 -2.5 inch outside
diameter and an inside opening of about 1.5-2 inch leaving a ring with a
thickness of about ¼ inch.
The only somewhat useful mold I found was a Colour de Verre re-usable
mold for napkin rings. While the created rings are beautiful, they
are too large and too thin for making the required cylinders. I tried it and
below is a picture of the molds before fusing.
I also made a circle, with the intent to drill the inside
opening out with a diamond hole drill. I found the risk of breaking the glass
and the work involved too much, and after creating rings I have not pursued that
technique any further.
It really comes down to making your own rings, or making
your own molds. I have considered many options and worked on some that work.
Two options that I probably will try is 1) using a stainless
steel muffin tray, burn in the tray in an oven, then lightly sandpaper
it and coat it several times with kiln wash for release. I will use a center
piece of pipe covered with fiber paper to create the opening and fill the
created ring with glass frit.
A second option is to use a stainless
steel donut tray. The size of the donuts fit with the requirements of
the size of the rings. Both the muffin and donut tray have a slightly conic
shape, facilitating the release of material from the mold. I believe I can
sufficiently shape any stack of rings with the jacks to create a cylinder.
Unfortunately, the problem with the donut tray is the nonstick coating that
all of them have and which has to be removed. This is yet another issue to be
addressed and I have placed in on the back burner.
Ringed
Bowls
The technique was invented by Boyd Sugiki,
I believe. Boyd turns out to be Jason Minami’s teacher, which explains a lot
of how both seem to “know” and “understand” hot glass. Boyd and Jason (as
well as Hannah) are these ultra-patient instructors who never seem to get
upset with a student. Not only do they understand glass, they understand
people also. Anyway, the technique of Boyd is as follows. He blows 2 or more
colored cylinders of equal diameter. After cooling, he cuts rings from the
cylinders with a diamond saw, re-stacks the rings into a cylinder again, but
now with different colored rings. He stacks the colored rings as a cylinder
in a kiln, heats up the stack until the rings are fused together. Then he
picks up the rings from the kiln on a blow pipe and heats the stack of rings
in the glory whole and blows and shapes it into a piece. You can see the
amazing result on Boyd’s
website. For instance his blown sculpture of
light and dark blue rings takes your breath away.
How do I know Boyd? He gave a course in making bowls at Glassroots. The details of this course can be seen online
in a video posted at the Corning
Studio website.
Powell Scott took the effort to video record his efforts
to create the rings which he calls the set-up, and then
blow the ringed bowl a
nine-ringed bowl no-less. It gives an impression, but not really the
skill and effort required, how to get to the final result.
Different
Ring Techniques
I contacted Powell which some questions about making the
rings, and he very graciously responded. My initial reaction was (what the
heck did I know about glassblowing?) if there were no other ways to make the
rings. Powell was not aware of any alternatives. I had considered 3
alternatives, without of course knowing the obstacles that these would
experience. 1) use glass frit (basically ground glass) in a ring mold and
fuse it in a kiln, This creates opportunities to
have different colors and patterns of colors in a ring. 2) use a glass rod,
drill a hole in it, stack the rings with holes in a kiln and pick it up, and
3) use glass sheet and cut or drill rings from these. The last options would
allow you to have very thin colored rings. I have modified this technique to
an easier path. That is, use clear glass rings cut from a cylinder and add a
thin ring cut from sheet between them. Or in the alternative have clear (or
colored) cylinder blown rings and add a thin layer of frit glass fused to it
in a kiln, I explain later why.
Here are two stacks of cut slices of a color rod with
holes drilled.
And my construction to drill holes in glass circles. I still have the
circles, but have not used them yet for a couple of years now.
Anyway, Powell was intrigued about the glass sheet rings.
And while I was still struggling cutting rings from sheet glass, he designed
a contraption to make the glass drilling easier and he actually created a
tumbler from these rings. It was an amazing piece of work and you can see it
at Powell’s Instagram
Account. Here are his pictures of that effort.
I can take credit for the idea, but the reduction to
practice (as it is known in patent vernacular) is clearly Powell Scott’s
achievement.
It also hit me that my glassblowing technique was not
advanced enough to actually try to create a ringed object as I was completely
unable to control shape, thickness and keeping rings parallel. So, I gave up
the ringed technique and had additional training in glassblowing technique by
Boyd Sugiki, Nadine Saylor and Jason
Minami. Instruction videos by Nikolaj
Christensen were also helpful.
State of
Technique
The following picture gives an impression of the state of
my skills later in 2022.
Ringed
Bowls Again
I still had a set of cut rings and I wanted to move on
from bottles to something else for a while. So, Charlie and I tried a novel
approach. The Glassroot hotshop
has a shovel-like implement on which I could put 4 rings next to each other
and heat it in the garage. After sufficient heating Charlie would stack the
rings on a piece of maple wood and I would blow a bubble into it. The rings
would sometimes not be hot enough or cooled too fast and would break when
blowing a bubble in it and drop off from the bubble.
A solution was to create a wooden mold that would hold
and align the rings and allowed the bubble to be forced against the inside of
the rings. Sometimes the rings would break, but overall
this worked. The following shows a picture of clear glass blown and cut rings holding an intervening
colored blown ring. After careful heating and blowing with an extra gather and
using Boyd’s bowl technique I would first get the following result.
You can see improving results of creating a parallel
structure during blowing from left to right. The better structure was created
by more aggressive paddling of the bottom right from the start on the pipe.
In order to better hold the rings or rather force the
rings on the bubble, I used a self-made wooden mold like shown below. It can
open and close, so the rings are forced into a cylinder shape when I blow a
bubble into it.
This method does work and with practice I got better and
better bowls. However, with the blown bubble it was not really possible to
work the inside and outside of the bubble on the pipe as the bottom was
closed off, of course.
In the
Kiln
I decided to give it a more serious approach and arranged
lessons with Jason Minami to get instructed on kiln picked-up cylinders.
Jason’s very first exercise was for me to create a more stable platform for
the stack to be fitted on the pick-up pipe. For the pick-up platform you take
a first gather from the furnace, hold up the pipe to let the glass flow back
on the pipe. Then place the pipe in the glory hole and blow until an opening
is created in the glass. Further open the opening at the bench and then hold
the jacks vertical and push the glass back on the pipe. Then shape the glass
on the pipe with the jacks or on the marver into a
cone shape. The pipe opening now sticks out. By cooling the so formed cone
and later heating only the top of the cone you have a more-or-less stable
relatively cool platform for the pick-up. Go to the kiln and pick-up the
stack.
This set-up makes a tremendous difference as the cylinder
does not flop around on the pipe after pickup. I then carefully heated the
cylinder and worked its inside and outside, shaping the end into a parison,
eventually closing the cylinder off. Later I would close the cylinder off
with a cookie dropped from a punty on the marver as not to lose colored glass to the bottom. There
are several other tricks I learned from Jason in this. All good. The most
counter-intuitive trick was not to push the glass off the pipe from the moil
after gathering. Many glassblowers do that in order to create a thin neck.
Jason’s technique is to keep the moil glowing hot. He calls it your “money in
the bank.” That keeps the glass fluid at the moil, while you cool the bottom
and then blow. The hot glass at the moil or neck will expand during blowing
and pulls the glass off the moil. With sufficient glass thickness everything
stays stable. In contrast when you strip glass from the moil all the glass is
at the bottom. Even when you don’t heat deep, the neck becomes more or less
fluid and makes the piece a flopping creation, causing a struggle to keep
everything stable.
Anyway, these are some of the results using Jason’s
lessons.
And here is another one:
I gave the “shovel” based approach another shot, but now
creating a stable cone on the pipe as taught by Jason before I blew a bubble
into the stack. This requires some careful work with the jack as you want to
create a stable pick-up platform with a bubble sticking out. The way I did
that is by creating a bubble from the first gather, then creating a neckline
near the edge of the pipe and pushing the glass back, and shaping the
remaining bubble into a cylinder that fits into the pick-up. This requires a
bit of exercise, but it works well. Below is an example of the result.
New Rings
All the above were made from rings cut from previously
blown cylinders, then cut, etc. I still want to use frit made rings. So, I
ordered stainless steel rings from Speedy
Metals, a small diameter internal ring and a larger size external ring,
to fill up the space with frit and fuse it in the kiln. I did the filling at the Glass Underground Studios
in Warren, NJ, where the staff is extremely friendly and helpful with my
projects. They helped me with selecting the right covering of the rings with
fiber paper for easy release after fusing and with creating the firing
schedule for the kiln.
Here are the rings in “uncovered” state.
And here on a firing board with rings covered and filled
with red and yellow frit. I make marks on the thin fire paper to align and
center the steel rings.
And this is the result after firing and grinding. The
white stuff is the residue of the fiber paper that washes off under water and
brushing it with an old soft toothbrush.
And this
is the result of the red/yellow stack blown into a bowl
I am told the result is very “artistic”. And I agree. But
from a technical point of view it is a failure.
Jason had already warned me that the frit rings are pure colors and have the
melting property of these “soft” or “hard” colors and bleed through during
blowing and are very difficult to control. The blown and cut rings have a strong base of clear
glass and have a more similar blowing behavior, making blowing and keeping
parallel rings easier.
Back to
the Drawing Board
There are several variations that work or may work. The first
one is to only use frit rings between blown rings. While perhaps not ideal, it
seems that the blown/cut rings will stabilize the structure, as compared to
using only frit rings. Well, that worked very well. The following picture is
of a bowl made from a combination of blown rings and frit rings. The result
was beyond expectations, with rings maintaining the parallel structure. You
can see one frit ring which was made from yellow and red frit.
One side effect is that the frit ring on the inside is
raw fused frit and uncovered by clear glass, as a result of the approach
taken. You can feel it, as it has a slightly rougher texture than the blown
rings.
Part of My Ring Set
The picture below shows a set of rings I already made.
Some are blown/cut, others are frit made. Also included is the remainder of a
red cylinder, which I can cut further if needed and a clear glass cylinder,
ready to be cut.
More
Rings
One approach taken, was to make clear rings from a clear
glass cylinder. Place the rings on a firing board, wrap it with slightly
higher fiber paper and hold it in place with pins. And then put a thin layer
of frit on each clear ring. Then fire the covered rings in a kiln.
Below you have the stack of rings created that way. Unfortunately the fiber paper dam is not very tight and
colored glass was seeping down.
But basically, you have clear rings with a thin cover and
some bleeding.
Here are the rings, picked-up from
the kiln and shaped and formed into a parison on a blowpipe. The ring
structure is well maintained.
And below this you can see the final result in the shape
of a bowl. The bleeding through is extensive. I call it the Bleeding Heart Bowl. But technically it works very well to
have thin colored rings in a clear glass object.
In fact, the
shadows demonstrate the very thin rings that have been formed as an inherent
part of the glass.
Here is a second bowl created in a similar manner. The
bleed-through is more controlled leading to a thin ring in a clear glass
set-up.
The following image shows a stack of sheet rings. Next, rather than
clear thin sheet rings I use also clear blown rings to create a stack.
Such a stack is shown next:
The rings will be ground to remove any burs. The bowl
created from this set-up is shown in the following image. The color rings are
thus a type of sheet insert.
The creation of these sheet glass rings is a pain in the
neck, and a bit dangerous, as the drill sometimes catches on the piece and
rotates it, so it become like a very sharp rotating knife. I always have
cut-resistant gloves on when I work with this set-up.
So, I the set-up was successful. Jason Minami heated a
stack of 1 inch high blown/cut clear rings, with inserted sets of 2 sheet
glass cut rings in a kiln to about 1250 F. I picked up the tack fused rings
on a blow pipe and created the following high bowl.
That worked extremely well. It also shows that the
intervening rings do not have to be sheet rings. The inside open diameter of
the color rings was smaller than of the blown rings, which contributed to the
expansion of the ring height. The diameter of the bowl is about 30 cm.
Next
Round
As every glassblower probably knows: there are at least
two aspects of glassblowing: 1) the technique/skills and 2) the artistic
execution. Next I want to expand some of the
technique but also use more colors and designs.
To that end I have created some wild colors cylinders, as shown next.
These cylinders are made from color overlays, with
contrasting sheet glass shards and blown out. Next
they were cut into rings.
My assumption is that during tack fusing the sheet glass
expands slightly. Based on that I have cut remnants of sheet glass into tiny
pieces and tack them to the upper surface of the cut rings by using Bullseye
glass glue (glasstac). Presumably the glue burns
off in the kiln.
Here is one of the cut rings with the pieces of (green) shards attached.
The rings are ready to go as a stack into the kiln. I am
already preparing other rings with combinations of different color sheet
glass. And then Jason Minami leaves Glassroots.
This is a setback, as my personal skills are somewhat shaky still. So, I need
to prepare for the next steps.
But, we will not give up.
To be
continued….
Fortitude
Strength of mind that allows one to endure pain or
adversity with courage. (see: http://www.thefreedictionary.com/Fortitudinous)
Lemma scientists, engineers and inventors
Sometimes one can use an unproven lemma and start
building a theory upon it; even though its correctness is questioned by
others.
Dissent from existing theory or practice, especially by
scientists or inventors who are not part of the "establishment" is
a known aspect of the history of science. Often, these researchers are
difficult people, sometimes identified as "crackpots". They often
challenge the fundamental beliefs of current science. Sometimes their
transition into acknowledged science is relatively smooth. Others may have
much more trouble.
With no significant source of income, often ignored or
ridiculed by contemporaries, they manage to lead the way into new directions.
Some of them receive recognition posthumously, even fewer receive recognition
during their life time. Many of them are forgotten.
In science, technology and engineering almost nothing is
easy. Every solution appears to bring its own problems. The safe way is to
remain on the proven path. To realize that the proven path may be wrong and
that a new approach may be required abhors many if not most people. It
usually means dissent, disagreement and struggle. Despite popular belief that
scientists embrace change and new theories, the opposite is arguably the
case. Exceptional efforts are made to explain new phenomena or to address an
apparent paradox with the tools and means of an existing theory, rather than
apply a new theory.
Developers of new theories are usually first vetted to
assess their status in the establishment. Different kind of pressures will be
brought to bear for the daring scientist to either recant the new theory or
at least to express severe doubts about its validity. Theorists from outside
the establishment may be ignored completely or are labeled as crackpots.
This attitude of skepticism is not unreasonable. There
are not that many truly novel and valid theories; many theories are truly
crackpot ideas, or supporting experiments are flawed. Experimental errors or
uncertainties have demonstrated to contribute to creating invalid theories.
The science community has demonstrated often the culpability to new unproven
theories to instill at least a sense of skepticism. Cold-fusion comes to
mind. Though, the skeptics were able to quickly disprove the occurrence of
that phenomenon.
To take a new path against disapproval of authority or
common belief is almost an impossible challenge. It takes an unbelievable
conviction, stubbornness, intuition and intelligence. And yes, fortitude.
Two influential "lemma scientists" who made a
tremendous impact on science were Joseph Fourier and Oliver Heaviside. They
are both connected to explaining transmission of signals. Both have developed
insights into fundamental aspects of mathematics which were initially doubted
and of which the theoretical correctness was eventually proven. What is
striking is how convinced both men were of the correctness of their
assumption and the tenacity with which they calculate their way to a
solution. Both men have written books with page after page of equations. A lesser
person would most likely have given up half way, being convinced that all of
this will lead nowhere. A nice overview of Fourier Analysis can be found in
The Mathematical Experience by Philip Davis and Reuben Hersh.
Oliver Heaviside
Oliver Heaviside is an almost forgotten
"self-taught" scientist. Almost forgotten, we should add, as many
of us still will recognize the name in the Heaviside Step
Function, much applied by Heaviside himself to investigate transmission
effects.
Heaviside should have been honored with a Nobel Prize.
There is no part of electromagnetic and electrical sciences that he did not
influence or help develop. The modeling of behavior of signals in electrical
network analysis as we currently apply is from his hand. His "lemmata" approach especially in his Operational
Calculus was often criticized, while he was fueling the flame of criticism by
maintaining that mathematics is an experimental science. However, no one was
able to come up with a better way to describe transients in electrical
transmission, until it was finally accepted that Laplace transforms could do
the trick. A publication on the Laplace transform, just before WWII, changed
the acknowledgment of Heaviside's contributions in standard Electrical
Network Analysis text. His name disappeared virtually overnight from
textbooks published post-WWII.
An instructive website comparing Heaviside's Operational
Calculus with Laplace transforms can be found at "Heaviside,
Laplace and the Inversion Integral". A more detailed explanation is
provided in "Heaviside
Operational Rules Applicable to Electromagnetic Problems" by I.V.
Lindell. It provides a further explanation of Heaviside's favored series
expansions.
Heaviside had an acid pen and a sharp tongue and his
polemics are still very funny to read. If you think your professor was
difficult: this was one scientist who did not suffer fools lightly. (see: the eminent scienticulist Preece). The same excellent site of www.archive.org also has some major
Heaviside works. Please visit this site
for Heaviside' Electrical Papers Part 2. This work contains some of the
comments by Heaviside on Preece's technical skills.
Not unlike Fourier Heaviside starts with some assumptions
and calculates his way to a solution. He started his scientific career with
working on his uncle's (Wheatstone) theory. With no formal training in
mathematics and physical theory he ends up with pretty much creating the
foundation of electrical theory and articulating electro-magnetic theory. Ido Yavetz in his excellent but
difficult to find book "From Obscurity to Enigma" makes the case
how Heaviside after going through extensive calculations always went back to
a fundamentally physical interpretation of the results. Yavetz
details Heaviside's belief in the existence of a transmission medium, perhaps
the aether, for propagating a field. In several
chapters Yavetz points at Heaviside's
"inability to resist a caustic remark". This is a great book, that
is now available in
a Kindle edition. Recently (2011), a cheaper paperback edition of this
excellent book has been published by Modern Birkhäuser
Classics.
Heaviside, a man of incredible brilliance and courage, a
superstar scientist and unjustly forgotten.
Paul Nahin wrote the
outstanding "Oliver Heaviside: Sage in Solitude" which I can
recommend to anyone who likes reading autobiographies, but even more so to
people who are interested in the history of sciences. Pupin received a patent
for inventing the "loading coil", which enabled long distance
transmission of signals of limited bandwidth without using amplifiers by
flattening and lowering the attenuation of a transmission line over the
limited bandwidth. The actual invention of the concept is by Heaviside,
picked up by several researchers such as John Stone Stone.
The reduction to practice is by George Campbell (the inventor of the
wave-filter). The patent and the money went to Pupin. Pupin was a highly
productive inventor. He was also pretty good at self
promoting and earned a Pulitzer price for
his autobiography. In this book he claims that his insights explain why radio
communication between planets would be impossible.
Because of the controversy it is easy to assume that
Pupin was a fraud. That he was certainly not. However
he was wrong at some occasions. For instance Pupin
obtained Patent
519,346 entitled "Apparatus for Telegraphic or Telephonic
Transmission" in 1894, wherein he claims improving the impedance by
adding capacity to cable sections. However, he got it somewhat right in and
obtained the relevant Patent
652,230 in 1900 over Campbell. He was a bright scientist and a gifted
inventor. His patents can be found on Google's Patent site. This
site is worth a visit as it allows searching on pre-1976 US Patents.
An analysis of the 'loading coil' affair by James
Brattain can be found in the book "The Engineer in America" under
"Introduction of the Loading Coil". An analysis what happened
inside AT&T in pursuing the 'loading coil' patent is described in
Wasserman's "From Invention to Innovation". Norbert Wiener was
upset by the treatment of Heaviside and wrote the book "The
Tempter". A highly recommended but difficult to find book is "From
Obscurity to Enigma: The work of Oliver Heaviside, 1872-1891" by Ido Yavetz. A very good book
that puts Heaviside in the context of articulating Maxwell's laws is
"The Maxwellians" by Bruce Hunt.
Preece receives a much more deferential treatment in Russell Burns'
book "Communications: An International History of the Formative
Years". Preece, at that time the
Engineer-in-Chief of the GPO, who is of course a very influential civil
servant, is more in support of Marconi than of Oliver Lodge. A understatement on page 296 is "Indeed, the
suggestion has been made that Preece was being
vindictive...." Oh, really? Reading Burns' book
one realizes that Preece was the contemporary of
Hertz, Lodge, Fitzgerald, Heaviside and Marconi. As a
"practical man" he consistently is on the wrong side of scientific
arguments. Still, he achieves a fairly exalted and influential position
related to the science of which he learns very little, it seems.
Oliver Heaviside is the named inventor on at least one
British Patent (No. 1,407) in which he establishes himself as the inventor of
coaxial cable to limit inductive coupling between adjacent cables. A
description of this patent can be found in Nahin's
book of which a
section can be found here. UK Patent 1407,
including the provisional specification can be downloaded by clicking here.
This copy of the Heaviside patent was found on the web-site of the German
Patent Office and can
be downloaded here.
The patent addresses the issue of inductive coupling. The
coaxial cable is actually one of several solutions that Heaviside provides to
this problem in his specification. His other solution is a cable with two
pairs of circuits, thus forming a 4 conductor-core cable. The filing date of
the patent is April 6, 1880. UK patents at that time did not require claims.
Though the Patent includes the declaration "...but what I claim is,
-" it does not have claims. Lacking enforceable claims and means to
pursue infringers in court, it must have been an almost insurmountable task
for Heaviside to pursue infringers on this patent. Heaviside probably, based
on this experience, must have decided that patents were not for him.
The above does not imply that we should pity Heaviside's
active period. First of all, Heaviside was not a man to be pitied. He was
quite opinionated and very well able to defend himself. Secondly, in a time
in history wherein certainly in Britain social class was extremely important,
Heaviside, without any formal education, positioned himself as a leading and
very much respected scientist who was recognized, corresponded with and
consulted on important and critical issues and at least the equal of other
scientific giants of that period. Heaviside's is a story that would fit very
well in an American rags-to-riches novel, with the exception that it took
place in one of the unlikeliest places. Britain, despite what we are
sometimes led to believe, actually has a history of offering leading
scientific positions based on merits, rather than class. Faraday is certainly
an example of that. However, it is sad that Heaviside was not able to convert
his scientific skills into at least some level of wealth or comfort as was
achieved by people like Thomson (Kelvin) and Pupin. This, I believe, made his
later period uncomfortable, certainly much less comfortable than he deserved,
and it affected his productivity and his engagement to scientific issues.
In a strange
write-up the IEEE contends that "As on (sic) old man, Heaviside spent
his final years comfortably, although his mental powers diminished. "I
have become as stupid as an owl," he once bluntly stated. Heaviside died
at the age of 74." IEEE editors should read the IEEE published
"Sage in Solitude" and remove that paragraph from their website.
Ohm's Law
Everything has to start somewhere. Modern network
analysis arguably starts with Kirchhoff. Kirchhoff was inspired by
Georg Simon Ohm, the discoverer of Ohm's law. How does one discover a law
like Ohm's if there are no voltage meters, no reliable or standard voltage or
current sources and no standard resistors? It was believed that if
there was something like a resistance, which was debated, then it would be a
dependency between current and voltage that was described by a logarithmic
relationship.
The story of Ohm is actually a fairly dramatic one. And
considering the importance and the brilliance of the discovery it is a fairly
unknown story. Joseph Keithley in his Electrical and Magnetic Measurements
book provides an outstanding essay on Ohm.
One may find more information on Ohm and Ohm's law on
this Wikipedia website.
The part that caught my eye was the statement that Ohm "He used a
galvanometer to measure current..." The Ørsted
effect, showing that the deflection of compass needle depends on a current,
was discovered in 1820. In the same year Johann Schweigger
built the first galvanometer, also called a multiplier or multiplicator. See
this website.
Excuse me.....when did this happen? And how?
Most of us know when something was invented. If not the
exact year, then at least a reasonable time frame, let's say within 20 or 30
years give or take. Ohm's law for instance is from 1826. His reliable and
actually quite consistent and repeatable power sources are thermoelectric
elements. In 1826.
What about the use of the first industrial
steam engine? That was in 1712. And not sometime in the early or mid 19th century as many people believe. It was invented
by Newcomen. The first steam engine was an absolute brilliant piece of
engineering and a demonstration of an almost unbelievable grasp of scientific
concepts reduced to practice. Contrary to what most people will tell when
asked how the first steam engine worked, the engine works under atmospheric
pressure. No technology existed at the time to create sufficient high pressure steam. A model of a Newcomen steam engine is
shown at this website.
The model is available as a kit. The website also shows a video of the
working model. The striking feature is the asymmetrical operation of the
engine. A nice description of the Newcomen engine can be found here.
The first
trans-atlantic telegraph cable? That one was
completed in 1858. The first
trans-atlantic telephone cable was not realized
until 1956, almost 100 years later. The technology for voice transmission was
much more of a challenge and radio transmission worked quite well and was
cheaper.
Formal switching expressions
While Boole is famous for Boolean algebra, he was
actually best known in his time for his methods of solving differential equations.
The Boolean algebra as applied in switching expressions is an invention by
Claude Shannon and presented in his Master
Thesis in 1936. Shannon provides several example circuits such as a
counter, a ripple adder and a factor and prime table generator including a
control circuit.
Complex is more likely than simple and not necessarily engineered
Engineers are trained to create technical solutions that
are efficient and perform their task with for instance the fewest possible
components. That is why certain structures and circuits are recognized as
being 'engineered.'
We are familiar with the concept of building complex
constructions from simple building blocks. An inherent assumption behind
creating complex structures is that availability of a set of certain
primitive building blocks is required. When we analyze (or reverse engineer)
the complex construction we should find the primitive building blocks. This
is such an elementary idea that it is probably for most people beyond
trivial.
Virtually all our thinking and analyses of naturally
occurring phenomena is based on finding the simplest element, the simplest
and smallest particle or expression. When things are complex
we want to reduce them to their simplest representation.
One example of such an engineering approach is in the
design of digital circuitry. Herein one may apply a representation of all
states of a circuit using primitive elements and eliminate all parts that do
not contribute to a required state. Karnaugh diagrams are used to minimize
circuitry.
The opposite approach is to use the maximum number of
different digital functions to create a simple digital design.
A fairly complex digital design is the one that
calculates a sum of two binary numbers. Such an expression has to calculate a
residue as well a carry for several cycles if the numbers comprise multiple
digits. The smallest addition of two single binary digits involves a XOR and
an AND function, which may be considered the primitive building blocks of a
ripple adder, which is what the name is of a full adder expression. The
simplest expression for a ripple adder is for the full addition of 2 binary
digits, which involves determining one residue and one carry digit.
So what, if one has run out on XOR and AND
functions? The next reasonable step is to create the XOR and AND function from adequate connectives, such as NANDs.
What if there are no NAND functions? It turns out that at that stage, one is
not able to create the simplest of simple ripple adders, which is the
addition of two bits.
It reasonable to assume
that an addition of two words of two bits with a ripple adder is more complex
than an addition of two bits. The reason for that is that additional layers
of interconnected logic have to be provided.
One simple, but time consuming
experiment, is to create and run a software program with the correct
structure of the 2 by 2 bits ripple adder (or any n by n ripple adder) and
start applying any of the 16 possible single binary logic functions (and not
the adequate connectives) but not the XOR and AND
function. One has to check all possible results of addition against the known
correct result, which is time consuming. Chaos is to be expected, right?
The surprising fact is that the more complex expression
of multi-digit ripple adders can be and are created from other than binary
XOR and AND single functions. So
while it may not be possible to use certain functions to create the simplest
device (the single digits tipple adder) it is possible to create the more
complex expressions.
From a logic perspective: complex is more likely than
simple! Furthermore, the more complex solutions are not what we would
generally consider to be engineered solutions.
Hiding in Plain Sight
One of the more intriguing developments by Heaviside is
the coaxial cable and the patent that he obtained. This patent (GB 1407) is
mentioned in all the leading biographies and technical books about Oliver
Heaviside. My impression was that I would have no problem finding a copy of
the patent on-line. Nothing of the kind. I did numerous extensive web
searches, mainly using Google, and came up empty. One obvious source was the
UK Patent Office (UK Intellectual
Patent Office) or even the European Patent Office. But, at least I was
not successful.
Finally, I found a
copy of the Heaviside patent here on (of all places) on the website of
the German Patent Office. And not through a
search of the site, but by going through an obscure folder listing of
documents.
The patent is very much worth studying. Not only for the
coaxial cable, but for its other solution to eliminate inductive effects. I
would say that the provided solution is a typical Heaviside one.
To my surprise, it is still very difficult to find a copy
of this patent by conducting a simple Google search. It is definitely there.
Hiding in plain sight.
Copyright 2008, 2009, 2010, 2011, 2013, 2015, 2016, 2023 Peter
Lablans. All rights reserved.
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