This morning I woke to Katsia`s concern that my car was missing. A brief investigation and a few calls to the police ascertained that it had been towed and was downtown. Great. Two hundred and eighty dollars later I was reunited with my car, only to then be presented with the original parking ticket. Apparently, despite being careful, my car was a whole 18" over someone`s driveway, and this was sufficient for a busybody bastard to call the cops and to get a $75 ticket for "blocking driveway"; and then for the towers to take it away just 40 minutes after the ticket was issued.
I am in two minds whether to pay the $75, as I do not live at the address to which my car and licence are registered, and no-one knows where I am. Ellie said that the police records may be tied to the border patrol, which is a serious concern. I`m grateful for any advice (no moral lectures, thanks).
I returned to Mountain View, Silicon Valley, to visit the fascinating History of Computing museum. This was a wonderful collection of all kinds of computing devices, from abacus through slide rules to vacuum-tube monsters to Crays to Ataris. It was like being back at JAS`s datacentre to see decades-old behemoth machines, stamped with "IBM" and collecting dust. Most of the computers I could not relate to, until I reached the 1980s machines, complete with 5.25" drives, 16-colour screens and software boxes that promised far more in terms of graphical output than could ever hope to be achieved in reality. I even saw an old monochrome Apricot like I used to own.
My favourite part was seeing a working example of Charles Babbage`s difference engine, a 5-ton monster created for, and loaned by, a Microsoft big-wig, who will mount it in his living room. I actually knew nothing of the machine, and was fascinated to learn that it was not designed to perform calculations ad-hoc, but to create printed tables of logarithms and sines (etc). It even has a built-in "printer" to create stereotype plates that can be used to print on paper.
(Non-techies can skip this) The engine works by calculating the Nth difference of a polynomial, up to N=7. It can therefore calculate solutions for polynomials up to the 7th power, after being primed with the first few results in the series. One simply turns a handle, and the differences are calculated for a given argument, and the results displayed and printed. HOWEVER, and this is a big `however`, the machine can only operate on integer coefficients in the polynomial. So if your problem is f(x) = 5x^2 + 3x - 5, then it`s easy; but if your series is, for example, the solution of a sine wave [sin(x) = x - (x^3)/3! + (x^5)/5! - (x^7)/7! + ...], with non-integer coefficients, then it needs a work-around. The work-around is to factor-up until one has only integer terms, and then divide-down the results that are printed out. Remember that this machine was supposed to create tables of sines and logs, not just easy integer polynomials, so having to use this work-around every time was not really all that wonderful.
There is a video of the machine in action, it`s really beautiful to watch the DNA-style rotations of the arms.
After the museum I went for coffee in Palo Alto with another uni friend, Ellie, who is post-doc`ing at Stanford. Again it was great to see a friendly face and to chat both about the old days and about being a Brit in California. I think she was tempted into further travels of America by hearing of my trip.
Haight-Ashbury is a section of SF where, in 1967, the hippie and LSD culture took off. Upon visiting today I saw that there were none of the expected gray-haired hippies, no perma-trip beatniks, and no free love. It`s mostly trendy clothing boutiques, record shops, and many bong shops. I was a bit disappointed: compared to my visit to Christiania in Copenhagen, where pot is grown, sold, and consumed in broad daylight; here in Haight-Ashbury it felt simply like Camden Town turned down a notch.
Now I am in the Green Tortoise hostel on Broadway, which I had forgotten was the street with all the strip clubs.
(If you would like to see all my computer photos, not just a selection, try Facebook: http://www.facebook.com/album.php?aid=20039&l=f196c&id=516724171 )