Dateline France, Report 27 13 September 1990 The last month in France I had two trips to Germany, one to Aachen for a couple days, the other to Berlin for a week. Quiz question of the week: Everyone knows where Checkpoint Charlie is. Where are Checkpoints Alpha and Bravo? Aachen is known for its hot springs, and equitation and jumping. There was a big jumping competition on when I was staying there. Aachen is also known as Aken and Aix-la-Chapelle, depending on what language you are speaking. It is located right at the juncture of Germany, Belgium and Holland. I was there at the invitation of Gottfried Vossen to visit the Technical University of Aachen and give a talk. The technical university has 36,000 students. Together with 9,000 students from another school, they make up 20% of the population of Aachen. The CS department has 6 faculty plus assistants, and 1400 majors. Most of them are in a 4 (or more) year program that gives them the equivalent of a master's degree. It would then be another 5 years or so as an assistant to a professor while earning a PhD. Another 5 years' work gets you a Habilitation degree, which is almost a requirement to be considered for an associate or full professor position. Hiring someone at a German university is a drawn out process. Lists of candidates generated in the department pass up the university hierarchy to the appropriate state ministry, which then sits on them a few months before issuing the offer letter. Once someone has an offer, there is no time limit in which they have to give a yes or no answer. Some people hold onto their offers over a year while negotiating. There are some funny rules that work against the applicant. You cannot have more than one offer in hand at a given rank, and you can't change universities after age 52 because of pension considerations. Aachen was the city from which Charlemagne ruled Europe. History time: Charles Martel was the mayor of the palace under the last of the Merovingen kings, Theodoric IV and Childeric III. He defeated the Saracens at Poitiers in 732. He managed to use the favor this earned him with the nobles to get his son, Pippin the Short, placed on the throne. Pippin wed Bertha Bigfoot and sired Charlemagne. This was the beginning of the Carolingian kings, who ruled France until Hugh Capet started the Capetian line, in 987. Charlemagne's first son was Louis I. The name Louis comes from the name Clovis of some of the Merovingian kings. There a cathedral near the central square, built in three parts. The earliest part was from around 800 and is pre-Gothic. It is built in a Byzantine style. Across the square from the cathedral is the town hall, which stands on the foundations of Charlemagne's palace. Further out from the center there are two large gates that are remnants of the wall around the town. One evening Gottfried took me up to a restaurant on top of a water tower on the top of a hill. This was better than the bar on the water tower in Brittany, because this one rotated. It make a revolution in a little less than an hour, giving us a view of other countries, large hills made from coal mining tailings, and a large teaching hospital that looks much like an oil refinery. ------ I was back in Berlin to teach a short course on object-oriented databases again. My first evening walking around I came across a computer store called "USA ACM Computers." I also noticed a subway stop called "Onkle Toms Hutte," but I never got down there to investigate where the name came from. Much of my first full day there (the Sunday before the course started) I spent at the Dahlem Museums. There are museums on the ethnography of Pre-Columbian America, Oceania, Africa, and Southeast Asia, and art museums for Indian art, Asian art, Islamic art and European painting and sculpture. Many Rembrandts and lots of wood sculpture. There was a special exhibit on German orders of knights. They were established in 1198, and were well established as the Prussian and Livland by 1400. Livland seems to be around present-day Latvia and Lithuania. The capital of these states was Marienburg. The knights maintained something called Balleis throughout the region, but I was unable to find the word in my German dictionary, nor did any of the German students in my class know what it meant. In 1525 the last Grandmaster of the Teutonic Knights ceased his rule, and the order went out of existence shortly thereafter. The other museum I visited that day was the Zucker (sugar) Museum. It started with exhibits on the chemistry of sugars. Then there were some displays on how the sugarbeet freed the slaves. The gist of the argument was that the emergence of the German sugarbeet industry made cane sugar from the colonies less in demand. That in turn meant fewer slaves had to be sent from Africa to harvest the cane. There was a diorama on processing of sugarbeets and a model of an old sugarbeet processing plant. This was followed by cases on the various forms of sugar and also by products, such as a Cuban newspaper printed on sugarcane paper. Before this century, almost all sugar was sold as hard, crystalized sugar loafs, mostly in large bullet shapes. The lack of granulation necessitated some kind of implement for breaking off pieces of the loaf, such as cutters, pliers and hatchets. At the end of Sunday I took a walk over to Brandenburg Gate--no more wall! The wall I had gotten chips from on the last trip was gone for hundreds of yards in either direction. You couldn't get up to the gate, though, because it was sheathed in scaffolding for renovation. The horses and chariots were gone from the top, apparently for restation. I wonder if they will turn them back around towards the west. Along most of this area there is still a second wall, one that was in East Berlin, setting off the no-man's land in between. There were several places where Germans could cross back and forth--nobody seemed to be asking for documents, although there were border police watching the crowds. I walked south towards Potsdammer Platz, where a huge stage was being assembled for a big John Waters concert, complete with tumbling wall, I was told. I watched the rows of Trabants heading home through the Potsdammer Platz passage. The building I taught in was on 17 June Street (Unter den Linden in East Berlin). This boulevard was lined every day with 100s of busses from Eastern Europe. Most were from Poland, but I did see a Lithuanian bus, too. The tourists on these buses seem only to be there to shop. Walking home in the afternoons I would see the throngs of shoppes returning, carrying their goods however the could--shopping bags, suitcases, shopping carts. Favorite items were beer, soda, chocolate, oranges, bananas and laundry detergent. Cigarettes didn't seem much in evidence, possibly because Poland grows lots of tobacco (although I heard it might stop when farmers can no longer get state-subsidized prices on fertilizer). Some stores have signs in them that they won't sell cases of items, I guess so they will have some stock left for regular customers. Consumer electronics were also much in evidence: boom boxes, VCRs, stereos, TVs, keyboards. One afternoon, in the 11 minutes walking back to my hotel, I counted 116 items go by me. Toshiba VCRs were the most common item. I saw two guys pulling a luggage cart with 7 of them. Either they came from a large family, or expected to sell them when they returned. It was like the weekly sales from Tom Peterson in one hour. This must be a boon to the Japanese and Korean electronics companies. All this consumerism made me wonder where the Poles were getting the hard currency for the purchases. One possibility was converting zlotys to east marks, then changing the east marks for west marks on the street in West Berlin. I asked one of my students who said another source was buying subsidized goods in East Germany and reselling them in the many impromptu street markets that had sprung up for that purpose in West Berlin. (The lower East German prices on things like children's wear had prompted requirements for proof of East German citizenship for purchase.) Wednesday evening I went to the Technical and Transport Museum. On the way I saw the M-bahn, a magnetic-levitation train with a 3-stop route. Real quiet. At the museum there was a new exhibit on Konrad Zuse, who had invented the digital computer in 1936 in his parents living room in Berlin. There was a working model of that Z1 machine. It was built over the past few years under the supervision of Zuse, as the original was destroyed by bombing in WWII. What it was was a large, programmable mechanical calculator. It was based on an ingenious linkage that turned out to be essentially an edge-triggered nand gate. The two inputs to the gates had to come at different times. What makes it unusual is that it used binary representation internally--floating point, yet! 16-bit mantissa, 8-bit exponent. It could handle decimal input and output, though. The operation set was load, store, *, +, - and /. I couldn't figure out how many storage locations it had. It had no branch instructions; it could only execute straight-line code, which was read from punched 35mm film. So not really Turing-equivalent, right? Except, except, you could join the film to itself to form a continuous loop. An interesting exam question--what is the computational power of arithmetic programs with a single repeat statement? The Z1 could be handcranked or powered by a motor. (How many modern machines have a manual override?) After the war, Zuse continued to build machines. In 1946 the Zuse company released the Z11, which was the first mass-produced relay computer. It is interesting to note that this early machine designer had studied architecture--buildings though, not computers. I saw several other exhibits. One was called "Kopfwerk"--"Headwork"--and featured the history of barber and beautician tools. The history of the hair dryer was great. Another exhibit was on textile machines. In a converted roundhouse were lots of train and boat exhibits. (The trains were mostly the real thing, the boats were all models.) Up on the third floor was an exhibit on stereoscopy. My favorite thing there was a hologram of a pair of binoculars where you could look through the binoculars when you got close up. Viewmaster was represented with both its reel viewers and stereo cameras they used to make. (Viewmaster is a Beaverton company.) The last thing I saw was some cases on scientific instruments made in Berlin. Short takes: Local English speakers refer to tourists who chip at the wall for souvenirs as "wallpeckers". Checkpoint Charlie was decommissioned while I was there. They just lifted the whole thing up with a crane and hauled it off somewhere. Quiz answer: Checkpoints Alpha and Bravo are at either end of the Helmstedt/Berlin motorway, leading from West Germany to West Berlin.