New and Improved
Last update: 23 March 2017
In 1837, Charles Babbage invented The Analytical Engine, a
mechanical card-programmed digital computer which anticipated almost
every aspect of the electronic computers which would not appear for
more than a century afterward. These pages are a virtual museum where you can
explore the Engine both through historical documents and an
emulator which allows you to experience for yourself what it
would have been like to program a steam-powered computer.
several new sample programs.
The longest continuously-running scientific experiment demonstrates that
even extremely viscous fluids will eventually flow as the liquids
they are. Do it yourself instructions are included.
An interactive animation illustrates how orbits around compact
objects such as neutron stars and black holes depart drastically from
Kepler's laws, and explains why.
eliminating the need for Java, and improves graphics rendering. The
original Java version
Retropsychokinesis is the claimed ability of certain subjects to alter
random data generated, but not examined, prior to the time
the data are presented to the subject. Crazy, you say!
Well, there's certainly no mechanism in mainstream physics which could
permit such an effect, yet experiments conducted by a number of
different researchers over the last 20 years suggest, compellingly
according to some
analyses, that the probability of the results obtained in such
experiments being purely the result of chance is sufficiently low
that they would be considered evidence of a causal mechanism in most
scientific disciplines. The archives of the Project provide a
broad collection of research reports (reproduced with the permission
of their authors and publishers) and literature citations
related to this elusive but, if real, profoundly important
You can explore the phenomenon of Retropsychokinesis (if indeed it
exists) through these on-line experiments. Each presents you with
a sequence of random data produced by the HotBits
radioactive random number generator which is presented by a
visual feedback program. The random sequence is
pre-recorded but not examined prior to your performing the
experiment. Results are logged in a secure and transparent fashion,
and a daily summary of results to
date is published on the Web. Complete source code is available
for all of the experiment programs.
eliminating the need for Java.
Organ lets you run interactive experiments which demonstrate how
the results from random data approach the normal
distribution expectation as the number of experiments grows large.
Update: HTML5 animation eliminates the need for Java applet
support. (The Java version
The history of
Autodesk and AutoCAD told through contemporary documents,
edited and annotated by Autodesk founder John Walker.
You can read this 900 page book
on-line on the World-Wide Web, or download a
copy to read or print off-line in either
or Adobe Acrobat PDF format.
New: Fifth edition (2017) updates to modern Web standards,
typography, and navigation.
In the late 1950s and early '60s Project Pluto aimed at developing a nuclear powered
cruise missile which could fly three times the speed of sound at low altitude with
unlimited range and deliver nuclear devastation to multiple targets with pinpoint accuracy. It
was one of the most bizarre concepts of the age of unlimited nuclear optimism, and got
as far as ground testing a full scale flight weight propulsion system.
If there is a pyramid of badassery when it comes to guns, the GAU-8 Avenger, carried
by the A-10 Thunderbolt II (“Warthog”) close air support aircraft, is
near the pinnacle. Explore the details of this bad boy.
Rocket engineering is complicated and demanding, but rocket
science is pretty straightforward. Explore the rocket equation,
which governs the operation of all rockets, and understand why it's so difficult
to get to orbit from the surface of the Earth and why multistage rockets
In the late 1950s, the U.S. Army investigated a flying saucer as an airborne replacement
for the ubiquitous Jeep. This is the story of the Avro Canada VZ-9 Avrocar, one of the
most curious projects of the “anything goes” era of aviation.
Before computers and calculators, there were slide rules. It is difficult for people today to appreciate just how magic it was to be
able to carry a small tool, made of bamboo and plastic, that could perform many of the computations of engineering and science which
used to be so tedious in mere seconds, as long as you were happy with its limited precision.
This document explores this vintage computing tool, using it to solve a variety of
problems ranging from loading a turnip truck to interstellar flight.
Essays about a variety of highly reactive and/or explosive molecules.
Don't try this at home.
Western politicians say, “We're not at war with Islam.”
But Islam is more than a just a religion. Its scriptures specify a
political system, civil and criminal law, economics and trade, laws of
war, and other matters which other major religions leave to civil
authority, and some of these policy prescriptions conflict with
Western values. This essay explores whether the West should treat
these aspects of Islam as an ideology, like communism, fundamentally
incompatible with its values, and how best to confront it.
Is Islam compatible with political freedom? This document combines
data from the Pew Research Center and Freedom House to investigate
how empirical evidence addresses this question.
Kerbal Space Program is a computer game in which the player builds
spacecraft, aircraft, and spaceplanes and sends them on various
missions. Not only is the game a great deal of fun, playing it helps
develop an intuitive sense for rocket design and engineering
and orbital mechanics, even among people who already understand these
topics at the mathematical level. The graphics in the game are
superb. This document is a collection of screen captures from
missions I've flown.
To understand the news about negotiations with aspiring nuclear
powers, it's important to grasp the technical fundamentals of
both paths to nuclear weapons. This document describes the science
and engineering behind enriching natural uranium for use in civil
nuclear power reactors or weapons. A companion document discusses
To understand the news about negotiations with aspiring nuclear
powers, it's important to comprehend the technical fundamentals of
both paths to nuclear weapons. Here are the physics, chemistry,
and engineering behind the production of plutonium for nuclear
weapons applications, described for non-specialists.
A companion document discusses
In an op-ed (never published) from July 1988 I ask whether the
government of the United States is losing its legitimacy: whether
citizens continue to believe it has the “consent of the
We decided to celebrate our fortieth wedding anniversary by going
South for the winter in January 2013. This being Fourmilab, no half
measures would suffice short of going all the way—to
the South Pole. We'd already
been to the North Pole so, hey,
we could become officially bipolar! This photo essay chronicles
There are many disadvantages to being a balding geezer. In
compensation, if you've managed to survive the second half of
the twentieth century and been involved in computing, there's bearing
personal witness to what happens when a
technological transition goes into full-tilt
exponential blow-off mode. I'm talking about Moore's Law—computing
power available at constant cost doubling every 18 months or so. When
Moore's Law is directly wired to your career and bank account,
it's nice to have a little thermometer you can use to see how it's
going as the years roll by. This page links to two benchmarks I've
used to evaluate computer performance ever since 1980. They focus on
things which matter dearly to me—floating point computation speed,
evaluation of trigonometric functions, and matrix algebra. If you're
interested in text searching or database retrieval speed, you should
run screaming from these benchmarks. Hey, they work for me.
New September 2012 update adds Haskell to the C, FORTRAN,
Visual Basic (6 and .NET) implementations of the original floating
point benchmark, and includes a comparison of the relative performance
of these languages.
This is a collection of postings from
and documents on this site
which relate to the paleo/primal/ancestral diet and lifestyle.
- Book Reviews
- Nutritional Supplements