Forth; firing teachers; propellantless drives; 39” hard drives; and other interesting matters


Mail 761 Friday, February 08, 2013

It’s pledge drive time at KUSC, which means that it’s also pledge drive time at Chaos Manor. Normally I don’t bug you about subscriptions, but at pledge drive time I do. This place operates on the public radio model. It’s free to everyone but it’s supported by subscriptions. If you haven’t subscribed this would be a good time to do it, and if you haven’t renewed your subscription in a year, this would be a time to do that. You have been reminded. Subscribe or renew now.

The radio is telling me that this will be a snow storm for the history books in New England. I am still scheduled to catch an airplane to Boston to be part of BOSKONE next Wednesday morning. We’ll see if the weather forces a change of plans. I expect things will have recovered by Wednesday morning, but you never know.


Triangulation interview.    [Note that for the first six minutes or so of the show, there is a typo in the on-screen caption which lists your Web site URL.]



Roland Dobbins

My interview with Leo Laporte from last Wednesday


Forth and WikiReader

Hi Jerry

Funny you should mention Forth the other day, I recently purchased WikiReader as it was priced right (originally $99 but now available on Amazon at $16.95)

It has a built in Forth interpreter, although the main WikiReader application is in C I believe. It’s all opensource software, and it runs for a year on 2 x AAA batteries. Simple touch screen user interface, a bit retro (no backlight or ports and only 3 buttons and the power switch) but handy to have the full text (no images) of wikipedia if you are unplugged for any reason. I wonder if it would be handy at the beach house. And you can write and run your own Forth programs, there is an emulator and once debugged you can install by putting them on the micro SD card which comes with it. A bargain I think

More details here (on Wikipedia of course… a bit recursive!

and here’s the Forth emulator

Some more here and here

The casing seems quite robust and, somewhat charmingly it is not quite square.


all the best


Something to look into. Thanks. FORTH has always been a very efficient language, but it can be a pain to debug complex programs. Of course FORTH users build a library of tested routines they can incorporate into their programs, and most FORTH users tend to work with specific devices. I understand it is still very much in use in astronomy. Thanks.


The buck stops with Ambassador Stevens!?!

Panetta’s response to questioning by Senator Graham is obscene. When asked who was in charge during the Benghazi attack, he says that it was not himself, Secretary Clinton nor President Obama. He says that Ambassador Stevens was the man in charge.

Carl Taylor

I would think that if the President told me “do what you have to do” and got out of the way, it would be a clear authorization to take charge. Were I Secretary of Defense I would call the theater commander and pass the order and authorization on to him; I wouldn’t expect the President to become involved in the details. It’s not his expertise. The local commander knows what assets he has, and what they can do. Give him the mission and get out of the way.

That did not happen. I do not know why. But I find it hard to blame the President in this instance. And I have known Panetta, not well but well enough to have some respect for his judgment and motives although we are hardly political allies. Someone should ask him why he did not pass along the order to do what you have to do.


Firing Teachers

Maybe firing the lowest-performing ten percent of teachers will improve a *bad* school. I doubt it will improve a *good* school.


In my experience it makes no difference; as the decision on who the ‘bad’ 10% are is made based upon who does the paperwork best, not who teaches best. For instance, if a teacher is late or inaccurate with the paperwork because they are spending time helping the slow students, or inspiring the class as a whole to good performance, that teacher become the ‘bad’ one. I think the paperwork is an attempt to measure the unmeasurable. This is because part of the learning process is based upon subjective performance measures. If a gifted student creates this grand symphony, how does one determine, in an objective fashion, this is ‘grand’ from a monkey (taught the basics of

harmonization) pounding on a piano?

If one is serious about it, it is not difficult to identify the really bad teachers. The students know. Yes, sometimes they will name a teacher who is ‘bad’ because the teacher insists on hard work and discipline, but not only do those cases stand out, but they are actually less common than you might think. In really bad schools where nearly everyone has given up there may be no good teachers – yet the technique works there too, or case histories show such. Reminds me of a well known personnel consultant technique: just showing that someone in management is interested and cares can change motivations and increase output in many employment situations. Of course measuring how good a teacher is by average performances on tests is fraught with danger, and unions rightly oppose it.

Yes: there is some art to choosing which are the 10% worst teachers, and certainly mistakes will be made. If the goal is perfection, failure is certain. Yet do not the students deserve some improvement in a school system deemed indistinguishable from an act of war against the nation?

Someone is going to be hurt by school reforms. Yet there must be reforms.


Affirmative action downside…

Charles Brumbelow

An inevitable downside, predictable and predicted.


Patenting ideas

Jerry P>I find my computer glasses (they are bi-focal) more comfortable around the house than my regular tri-focals, although I certainly don’t wear them outside and it would be a disaster to wear them for driving. I sure wish I had patented the concept. Probably wasn’t patentable. But I think that old BYTE column was the first place to talk about compouter glasses. Certainly I don’t remember any source for the concept, and I think I invented it.

I can’t believe you are saying this seriously. And wishing for the ability to patent such a trivial "invention". The invention of "software patents" in the 1970s OTOH was not only non-trivial, but devastating for software innovation, granting government monopolies to visionless entities like Bill Gates’s Microsoft, which survive and thrive, not by continually improving their software and occasionally coming up with something really new, like dozens of microcomputer software companies did in the 1980s, but by filing patents on hosts of trivial ideas implemented by routine coding within the grasp of any competent programmer, then defending them with a stable of lawyers, backed by infinitely deep pockets. As a result, there was more software innovation in any given year of the 1980s, than there has been in the last ten years (note I am not talking about innovation in the use of software, which has been widely democratized over the internet, past any possibility of government regulation). Software patents are pretty much a U.S. invention, since they’re not recognized in Europe or anywhere else that I know. But this shouldn’t be surprising in a nation in which all the money flows to lawyers, politicians, and those who are in a position to manipulate the law in their favor, with maybe just a bit of trickle down to the actual inventors and creators, just to make the whole scam look legit.

As for the "invention" of computer glasses, how is the concept any different from the "invention" of reading glasses for older people at whatever convenient focal length? Do you wish that you had patented reading glasses at the 28" focal length? Well, if so, I’ve got you beat, since when I had my first cataract operation some seven years ago, I had my implant set to 27", which was my measured distance from the screen. When I had my second cataract operation a couple of years ago, I had the other eye set to my preferred book reading distance. To complete the adjustment, I have two pairs of monofocal glasses at, respectively, computer distance and book reading distance; in fact they are essentially monocles in a pair-of-glasses frame, since each pair of glasses has only one lens, the other prescription being covered by my cataract implant lens. Since in a pinch, I can drive with my eyes set to 27" (there’s not that much difference between 27" and infinity), I can get along without glasses altogether, if I have to, though I would not want to spend many hours doing anything intensely visual without them.

So, should I have the right to patent single lens glasses (ignoring the fact that once, before the time of software patents, monocles were very popular)? Or perhaps I could patent the whole two cataract adjustment as a glassless system for older people? I could turn this into a software patent by writing a program that engaged in a dialogue with an aging person eligible for cataract surgery, in which I would guide him in determining and measuring the two most useful focal lengths, then print out instructions to the ophthalmologist. I could refine and optimize the system a bit by determining also which was his dominant eye, and what his corrected vision was in each eye, so as to optimize for choice of eye as well as for focal length. If anybody at Microsoft had ever thought of that, I could perhaps have been sued for daring to do my own thinking about these everyday life problems. Well maybe not now, but the way things are going, with everybody looking to government to award them something for nothing, at everyone else’s expense….

John B. Robb

Great heavens. One would think I had actually attempted to get a patent. Or a trade mark which could be sold. I don’t really think I owe an apology for idle speculation.

Of course there is a real point here: it is the case that patents are sometimes, perhaps often, issued for matters that ought not be patented, which is to say that the patent office is not infallible. And there are patent trolls who impede progress. But then a long time ago Dr. Sivana was able to copyright the letter ‘e’ and Captain Marvel was obliged to defend his rights, and it sure did make for ethical conflicts, and




Counting raindrops

How to use mobile-phone networks for weather forecasting

Feb 9th 2013

FORECASTING the weather requires huge quantities of data. Many of these data are collected by high-tech means such as satellites and radar, and then crunched by some of the world’s fastest supercomputers into predictions that are far more accurate than they were 20 years ago. But low-tech tools are important too—especially old-fashioned rain gauges, which are nothing more than tubes with funnels fixed to places such as rooftops.

Each technique has its upsides and downsides. Radar and satellites can cover swathes of land, yet they lack detail. Gauges are much more accurate, but the price of that accuracy is spotty coverage. Now, though, Aart Overeem of the Royal Netherlands Meteorological Institute and his colleagues reckon they have come up with another way to keep an eye on the rain. It offers, they believe, both broad coverage and fine detail. Best of all, it relies on something that is already almost omnipresent—the mobile-phone network.

Their scheme starts from the observation that rain can make it harder for certain sorts of electromagnetic radiation to travel through the atmosphere. Measure this impedance (and scrub out any other sources of variation) and you can measure how rainy it is. The researchers do not measure the strength of mobile-phone signals themselves. Instead, they piggyback on something that mobile networks already do, and measure the strength of the microwave links that base stations use to talk to each other.

The idea itself is not new, and there have been trials in recent years. But, as they report in the Proceedings of the National Academy of Sciences, Dr Overeem and his colleagues have successfully applied the technique to an entire country. Using data from around 2,400 links between base-stations belonging to T-Mobile, one of the Netherlands’ three mobile-phone operators, they were able to generate a rain map of the whole kingdom every 15 minutes.

Like all the best science, the idea is both technically elegant and practically useful. Dr Overeem points out that simply coming up with another way to measure rainfall is handy by itself, since it allows better cross-checking of existing methods. There are other advantages, too. Coverage is one. Even in rich countries with well-financed weather forecasters, there are likely to be far more mobile-phone base stations than rain gauges. That is truer still in poor countries, where rain gauges are scarce and radar often nonexistent, but mobile phones common. The GSM Association, a mobile-phone trade group, estimates that 90% of the world’s population lives within range of a base station.

Another boon is that network operators tend to keep a close eye on their microwave links. Although the researchers were able to obtain data only every 15 minutes, some firms sample their networks once a minute. That means rainfall could, in principle, be measured almost in real time, something that neither gauges nor radar nor satellites can manage.

The technology is not perfect: snow and hail are harder than rain for microwaves to spot, for example. And there are other caveats. Mobile networks are densest in urban areas, which are also the places most likely to have meteorological equipment already. Even in the rich, urbanised Netherlands, coverage outside cities was noticeably patchier. But that might eventually prove to be a boon, for if the technology becomes widespread then weather forecasters might contribute to the cost of installing base stations in coverage blackspots—something for which the 10% of humanity not yet within range of a mobile-phone mast might be thankful.

Clever indeed. Thanks.


Seen on Slashdot

The URL is highly misleading, no doubt deliberately so. The title is “EmDrive: China’s radical new space drive”.

From the article: “The latest research comes from a team headed by Yang Juan <> , Professor of Propulsion Theory and Engineering of Aeronautics and Astronautics at the Northwestern Polytechnic University in Xi’an. Titled "Net thrust measurement of propellantless microwave thruster," it was published last year in the academic journal Acta Physica Sinica, now translated <> into English.”

Key word: propellantless. This is not a typo. This thing allegedly uses no reaction mass.

And some of what the article describes reminds me distantly of the Dean Drive, and Harry Stine’s description of the theoretical work he and others did at Huyck trying to figure out how to make it real and practical.

–John R. Strohm

I think I would want to see a working demonstration before investing any serious money in this…



Hello Jerry,

This was on ‘Drudge’ today:

Again, the question that not a single ‘mainstream journalist’ is asking is ‘Why?’. A huge laundry list of federal agencies that apparently had few or no requirements for hand guns, assault rifles, and massive quantities of ammo in the past now have requirements for all of the above. Since they have been in business for years WITHOUT the requirement, how has their missions changed so that they now require war-fighting levels of armament and ammo (except that the ammo is illegal for war)? And, a related question that is evoking exactly zero mainstream media interest: "Why is much of the ammo being purchased from companies that came into existence days before the contract was awarded and have no physical presence–offices, personnel, nothing–except government contracts for guns and ammo?

Bob Ludwick=

Why indeed?



Hello Jerry,

Since their inception, Marxists have ALWAYS used elimination as the ‘gold standard’ method for dealing with dissenters. Why should we suppose that OUR Marxists are in some way ‘kinder and gentler’?

This is a piece on what the administration is up to, including an embedded video hosted and narrated by the First Lady. Both the article and the video are ‘interesting’. As in the context of ‘May you live in interesting times!’. :

And then ‘The American Thinker’, noting that in the last six months alone the administration has purchased 1.4 BILLION rounds of small arms ammo, most of it hollow point ammo that is outlawed in international conflicts, asks the obvious question:

Just as a matter of interest, the ammo expenditure rate of the military (from the article, unconfirmed) in Iraq and Afghanistan is around 70 MILLION rounds/year. In other words, just in the last six months DHS has bought enough ammo to supply the combat ammo requirements of our military for 20 years at the current rate of expenditure. Inquiring minds, at least those of the mainstream media, have less than zero interest in discovering what DHS intends to shoot it at.

Bob Ludwick


‘Stanford and Bradley say evidence for the Solutreans’ presence in America includes stone artifacts gathered by archaeologists at several sites on the eastern shore of Chesapeake Bay, all producing dates more than 20,000 years old.’



Roland Dobbins

Fascinating. Of course Niven and I have the New World populated by a magic aware sort of bronze age civilization 14000 years ago just after Atlantis sank. And then I found that terror birds really existed at that time. I rather like what we did with them in Burning Tower.



Here is the new cutting edge reading technology. The bio-optically scannable book!

(in Spanish with subtitles)



39-inch hard drive platters in 1965…

Hi Jerry,

I hope you are well. I value your column and thoughts as always.

On the topic of computer technology during our lifetimes, I thought you might be amused and amazed by this two ton hard drive with 39" platters (8 MB each):

They only needed 20KVA at 440VAC for 1200 RPM operation. I assume that these were the largest hard drive platters ever produced… have you ever heard of anything larger?


-John G. Hackett

Back in the 1980’s I was on the Board of the Lowell Observatory (in Flagstaff), and when I went to my first board meeting I found the Shoemaker had his asteroids and comets on a pair of DEC removable platter hard drives, I think not 39” in diameter, but perhaps 24”. The drives were in a case the size of a 4-drawer file cabinet. I replaced them with some 300 megabyte Winchesters that I got Priam and some other drive makers to donate. DEC had given them to us, but we were paying several thousand a month in maintenance for them; but until I got the Winchesters they were the only thing Shoemaker could use large enough for his data.


English history and U. S. Law

Dr. Pournelle,

Alongside or in tune with the effect that the English succession had on the first amendment, pertinent to today, was the effect James had on the development of our own second amendment. If he had not tried to disarm his powerful opposition, our founders might never had thought of the need for it.



"What bravery its directors displayed over that time, so that the institution could stand tall and successfully complete its production and social tasks!"


Roland Dobbins


It’s pledge drive time. This place operates on the public radio model. It’s free to everyone but it’s supported by subscriptions. If you haven’t subscribed this would be a good time to do it, and if you haven’t renewed your subscription in a year, this would be a time to do that. You have been reminded. Subscribe or renew now.




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