Have you ever thought about coffee purity? It’s more something you’d encounter with prescription or elicit drugs, but coffee is actually a rather valuable commodity. If a seller can make the actual grounds go a bit further by stretching the brew with alternative ingredients there becomes an incentive to cheat.
If this sounds like the stuff rumors are made of, that’s because it is! Here in Ho Chi Minh City there are age-old rumors a coffee syndicate that masterfully passes off adulterated product as pure, high-grade coffee. Rumors are one thing, but the local media started picking up on these suspicions and that caught my attention. I decided to look to simple chemistry to see if I could prove or disprove the story.
What we want to investigate is whether price and coffee purity are related. If they are, then after accounting for the effect of price, we will want to know whether proximity to the market where artificial coffee flavoring is sold has an effect on coffee purity.
In an era where we can watch rockets land on their tails Buck Rogers-style live on YouTube, it’s difficult to imagine a time when even the most basic concepts of rocketry were hotly debated. At the time, many argued that the very concept of a liquid fueled rocket was impossible, and that any work towards designing practical rocket powered vehicles was a waste of time and money. Manned spacecraft, satellite communications, to say nothing of landing on other worlds; all considered nothing more than entertainment for children or particularly fanciful adults.
Walter Dornberger (Bundesarchiv, Bild 146-1980-009-33 / CC-BY-SA 3.0)
This is the world in which V-2, written by the head of the German rocket development program Walter Dornberger, takes place. The entire history of the A-4/V-2 rocket program is laid out in this book, from the very early days when Dornberger and his team were launching rockets with little more than matches, all the way up to Germany’s frantic attempts to mobilize the still incomplete V-2 rocket in face of increasingly certain defeat at the end of World War II.
For those fascinated with early space exploration and the development of the V-2 rocket like myself, this book is essentially unparalleled. It’s written completely in the first person, through Dornberger’s own eyes, and reads in most places like a personal tour of his rocket development site at the Peenemünde Army Research Center. Dornberger walks through the laboratories and factories of Peenemünde, describing the research being done and the engineers at work in a personal detail that you simply don’t get anywhere else.
But this book is not only a personal account of how the world’s first man-made object to reach space was created, it’s also a realistic case study of how engineers and the management that pays the bills often clash with disastrous results. Dornberger and his team wanted to create a vehicle to someday allow man to reach space, while the Nazi government had a much more nefarious and immediate goal. But this isn’t a book about the war — the only battles you’ll read about in V-2 take place in meeting rooms, where the engineers who understood the immense difficulty of their task tried in vain to explain why the timetables and production numbers the German military wanted simply couldn’t be met.
Your fancy white electronic brick of consumer electronics started off white, but after some time it yellowed and became brittle. This shouldn’t have happened; plastic is supposed to last forever. It turns out that plastic enclosures are vulnerable to the same things as skin, and the effects are similar. When they are stared at by the sun, the damage is done even though it might not be visible to you for quite some time.
Bill Shockley brought the transistor to a pasture in Palo Alto, but he didn’t land there by chance. There was already a plot afoot which had nothing to do with silicon, and it had already been a happening place for some time by then.
Often overshadowed by Edison and Menlo Park or Western Electric and its Bell Labs, people forget that the practical beginning of modern radio and telecommunications began unsuspectingly in the Bay Area on the shoestring-budgeted work benches of Lee de Forest at Federal Telegraph.
As the first decade of the 20th century passed, Lee de Forest was already a controversial figure. He had founded a company in New York to develop his early vacuum tubes as detectors for radio, but he was not very good at business. Some of the officers of the company decided that progress was not being made fast enough and drained the company of assets while de Forest was away. This led to years of legal troubles and the arrest of many involved due to fraud and loss of investors’ money.
When writing a recent piece about Reverse Polish Notation, or RPN, as a hook for my writing I retrieved my Sinclair Scientific calculator from storage. This was an important model in the genesis of the scientific calculator, not for being either a trailblazer or even for being especially good, but for the interesting manner of its operation and that it was one of the first scientific calculators at an affordable price.
I bought the calculator in a 1980s rummage sale, bodged its broken battery clip to bring it to life, and had it on my bench for a few years. Even in the early 1990s (and even if you didn’t use it), having a retro calculator on your bench gave you a bit of street cred. But then as life moved around me it went into that storage box, and until the RPN article that’s where it stayed. Finding it was a significant task, to locate something about the size of a candy bar in the storage box it had inhabited for two decades, among a slightly chaotic brace of shelves full of similar boxes.
The Sinclair’s clean design still looks good four decades later.
Looking at it though as an adult, it becomes obvious that this is an interesting machine in its own right, and one that deserves a closer examination. What follows will not be the only teardown of a Sinclair Scientific on the web, after all nobody could match [Ken Shirriff]’s examination of the internals of its chip, but it should provide an insight into the calculator’s construction, and plenty of satisfying pictures for lovers of 1970s consumer electronics.
The Sinclair is protected by a rigid black plastic case, meaning that it has survived the decades well. On the inside of the case is a crib sheet for its RPN syntax and scientific functions, an invaluable aid when it comes to performing any calculations.
It shares the same external design as the earlier Sinclair Cambridge, a more humble arithmetic calculator, but where the Cambridge’s plastic is black, on the Scientific it is white. The LED display sits behind a purple-tinted window, and the blue-and-black keyboard occupies the lower two-thirds of the front panel. At 50 x 111 x 16 mm it is a true pocket calculator, with an elegance many of its contemporaries failed to achieve and which is certainly not matched by most recent calculators. Good industrial design does not age, and while the Sinclair’s design makes it visibly a product of the early 1970s space-age aesthetic it is nevertheless an attractive item in its own right.
There’s a time in every geek’s development when they learn of Conway’s Game of Life. This is usually followed by an afternoon spent on discovering that the standard rule set has been chosen because most of the others just don’t do interesting things, and that every idea you have has already been implemented. Often enough this episode is then remembered as ‘having learned about cellular automata’ (CA). While important, the Game of Life is not the only CA out there and it’s not even the first. The story starts decades before Life’s publication in 1970 in a place where a lot of science happened at that time: the year is 1943, the place is Los Alamos in New Mexico and the name is John von Neumann.
The ‘cellular’ part in the name comes from the fact that CAs represent a grid of cells that can be in a number of defined states. The grid can have any number of dimensions, but with three dimensions the visual representation starts to get into the way, and above that most human brains stop working, so two-dimensional grids are the most common — with the occasional one-dimensional surprise. The cells’ states are in most cases discrete but a subset of continuous CAs exists. During the operation of a CA the future state of every cell in the grid is determined from each cells state according to a set of rules which in most cases take into account the states of neighboring cells.
When we think of role models, it’s easy to categorize them narrowly on the basis of their skill set. We might say that he’s a great mathematician, or that she is an excellent chemist. Some role models are admirable on a deeper, human level. These are the kinds of heroes who obliterate all the obstacles dropped in front of them to tirelessly pursue their interests and devote their lives to doing the kind of stuff that makes the world better for everyone.
Italian Nobel Laureate Rita Levi-Montalcini is this kind of role model. Her scientific curiosity and unconventional thinking led her to discover nerve growth factor (NGF), a naturally occurring protein which we now know is responsible for nerve growth and regulation. Rita’s discovery provided great insight into the way the nervous system develops. The discoveries that she made underlie much of modern research into neurologically degenerative diseases like Alzheimer’s and cancer, and NGF is used experimentally the treatment of both.