Saturday, 27 September 2008

Seth Efrica

So the reason for the silence is that we've been in South Africa for a couple of weeks. I'm planning to do a web page with lots of photos, so my mum can nostalge (she was born there, too), but that's a major undertaking, so I figured I'd do a blog posting with half a dozen photos so you can see where I've been. Sadly, I'll not be able to finish the post until Monday Tuesday, so I'm doing a bit as and when I can, and hoping Blogger will take care of me. Yes, I keep hitting Save Now.

Jenny had been invited to be keynote speaker at the biennial conference of the Pal├Žontological Society of South Africa (PSSA), which was all the excuse we needed. Having arrived around 09:00 in Cape Town where it was colder than the UK and raining, we failed to check into our hotel as we were far too early. Bummer! Undaunted, we drove around the peninsula, visiting the nature reserve at the southern end, where we saw lots of interesting plants and a few birds, like a pair of ostriches, an orange breasted sunbird and a black shouldered kite.
The next day we drove 250 km northeast from Cape Town to a tiny place called Matjiesfontein, where the conference was taking place. On the way, we drove through the mountains near Paarl where we were surprised to see snow on the mountains. Don't remember that from when I was a kid.

We stopped for lunch at a picnic spot, and I put the previous night's foil-wrapped leftovers on the car engine, which I left running, but VW have been much too efficient at keeping the heat inside the engine, and after 10 minutes they were still stone cold. We settled for nuts, fruit and a beer for lunch.

They'd had more rain than usual in the Karoo, and our timing was perfect, so we saw sheets of wildflowers on either side of the road as we drove. The photo's don't really do it justice, but at least you can get the idea.

On the afternoon of the first day of the conference I drove into the nearest town. Not being a conference delegate, that was fine, and my critical need was for some AA batteries, as the ones in the camera had run flat and the shop in the village sold almost nothing you could possibly want, and certainly not AA batteries!

I hoped to find a petrol station before I got to Laingsburg, 25 km away, but it was not to be. In Laingsburg I bought 4 batteries for 9 Rand, and clearly didn't have my brain engaged as I did so. R9 is about 60p, which is what they were worth, I discovered. (14 Rand = £1)

I drove half-way home and stopped to photograph the flowers, only to find I'd flattened the batteries. I took them back, of course, and bought some Energizers, for an additional R34. Proper batteries!

Half-way back I stopped again, and then did a bad thing. Pointing the camera diagonally out of the front windscreen, I drove along a promising stretch of the road, filming as I went. On a straight, lightly-trafficked road, it wasn't particularly dangerous, but I know I shouldn't have done it. The veldt isn't exactly a blaze of colour, but you do get an impression of what we could see. The truth is, though the edge of the road is the only place you see the flowers in the movie, in fact the whole veldt is full of flowers, but the orange ones predominate the near perspective.

So I did a round trip of 75 km to buy 4 AA batteries. Nice to keep things in proportion!
videoI've no idea why Blogger decided to only let me put 1 line of text next to the movie. It's a mystery.
Outside our bedroom window were two big trees, in which male Cape weaver birds were building nests and displaying to the females. So naturally I had to get that on film, didn't I? They were quite noisy, but fortunately not enough to wake us at dawn, so we weren't really disturbed by them. Sadly, blogger is unable or unwilling to let me upload the movie, so a photo will have to do.

There were also little swifts nesting under the eaves. It took me a while to identify them, as there are several pages of swifts, martins and swallows in our SA bird book, and of course, they're all pretty similar to each other.

Edit: Though curiously, swifts are more closely related to humming birds than they are to swallows and martins.

The Hotel Milner was built in Victorian times and renovated in the 1970's, but is now in its second decline. The sash windows rattled in their frames and even when we'd wedged bog paper into the cracks, the glass rattled in the wood, where the putty had fallen out.

The water supply was a bit iffy, too. On the second day the cold water poured into the bath pre-browned. Lovely. I'm sure there was nothing wrong with it, but it wasn't particularly appealing!

The staff were very friendly, courteous and helpful, so we didn't complain. Good staff can compensate for many ills!

After the conference there were two days of field excursions, looking at fossil-yielding sites that various people knew about. Naturally, if you go to a well-known site, you're unlikely to find much, since the locals have already picked it clean.
However, one site we visited had never been checked at all, and we were quite excited at the prospect of finding dinosaur bones there. Sadly, though the day was bright and sunny and the canyon we walked was very beautiful, nobody found anything much at all.

The guy who'd got us all there, Billy de Klerk from the Albany Museum in Grahamstown was not dismayed at all, but we were rather disappointed.

The track to the site was extremely rough and we had to leave our cars at the farmhouse and go in 4x4s. Some of the way back I did in the back of the farmer's bakkie (flatback pickup), which is something you have to do at least once in your life. It's normal transportation for many farm workers in South Africa and would be completely illegal in the UK, since there are no seats in the back, let alone seat belts. The health and safety jobsworths would have a field day! Fortunately I only went in the bakkie on normal roads, not on the really rough stuff.
After the field excursions, Jenny and I drove to Grahamstown, where she did some work at the Albany Museum with Rob Gess, who has found some interesting fossil fish in a road cutting nearby. Rob and his wife Serena are a really nice couple who took great care of us all the while we were in Grahamstown. The red flowers are on a coral tree, of which there are lots in Grahamstown. It was a little early in the season for them so the show wasn't as good as it might have been. Also much too early for the jacarandas the town is abundantly planted with.

At the weekend they'd planned to take us canoeing, but it was bitterly cold, and doing things that get you wet on days like that is not to be recommended, so we headed for a fossil-yielding site he knew. It was a long way down a dirt road, and then when we arrived, it started to rain. After quite a short time it was absolutely sheeting down and we decided that there was a risk the VW Polo I'd hired from Avis would not cope with the dirt road on the way back if the rain kept up, so we skedaddled. The car coped admirably, even if I did bang various underneath bits on the road from time to time.
They took us to a deserted beach where, while the rain continued, albeit less heavily, we sat in their car eating rolls and drinking tea. The wreck is of a fishing trawler and is slowly falling apart.

Serena, who drove their car all the time, is a passionate birder, and managed to drive and spot birds constantly. I usually drive off the road when I try to do that! Every now and then she'd slow right down and point out of her window at something - a jackal buzzard carrying off some small prey, a pair of Egyptian geese, and so on.

On the Sunday we headed inland for about 50 or 75 km and stopped in a road cutting. We'd missed the turning they'd been heading for, as the roadsign had been stolen (anything metal that can be moved tends to get stolen and sold for scrap) and we actually stopped just to discuss what to do. In the event, it was the right sort of rock, so we stayed there and looked for fossils. The expected beasts are 200 million year old mammal-like reptiles from the Permian, for which SA is very well known.

Now Jenny and I are not bad at finding fossils, but our performance on this occasion was unimpressive. Quite quickly, Rob found a leg bone maybe 10 cm long, so we had a look to help us get our eyes in, then went back to looking.

After extracting the leg bone, Rob carried on, and soon found a pelvic girdle. We continued to find nothing. Not long after that he found a skull, which took him several hours to extract. We maintained our 100% failure record.

Later in the afternoon we tried to get to the site they'd originally been aiming for, but this entailed yet another dirt road. As the road got rougher and rougher, I eventually had to give up or I'd have left the poor Polo balanced on a rock with all 4 wheels off the ground! We tried an alternative route, but that defeated me too.

Eventually we drove slowly back towards the main road, stopping every now and then when we spotted the right sort of rock cropping out of the veldt. Naturally, Rob found another leg bone, this one rather bigger than the first. We found nothing, of course. Actually, that's not entirely true. I did find a section of plant fossil, a small piece of a biggish horsetail.

Curiously, despite having found more or less nothing, we had still had a thoroughly enjoyable day, helped by wall to wall blue sky and reasonably warm sunshine.

Finally, we flew home on the Tuesday, first from Port Elizabeth to Johannesburg, then on to LHR. Our hearts sank as we saw the two small babies next to us, but they were as good as gold and we hardly heard a peep out of them all night.

So I am now completely knackered. On Wednesday, having just returned, we ate in the Thai restaurant with Lorna and Richard. Then on Thursday it was Peter's birthday, so we ate out in the Chinese. Friday we sang in a concert, Saturday we had our last barbie of the year and last night we went to an amdram play, followed by excellent food and company at Peter and Julia's, celebrating his birthday again!

The concert was part of Royston Festival and we only just got away with it. We've not been so under-rehearsed for ages, and were extremely lucky that almost everything held together. The concert was focused on the Virgin Mary, so if you look at the programme you'll see several Ave Marias and Ave Maris Stellas. The music was interspersed with readings of historical and other documents, and all in all, was not bad. Jenny and I had done some notebashing, particularly of the Poulenc, and that paid off, I'm glad to say. It was a bit heavy on God for my taste, but then, it was a Virgin Mary concert. At least we were spared prayers.

Tuesday, 9 September 2008

Disaster!

About 15 years ago I made this buckle. It's cast silver, and represents the skull of a Babyrusa, which is a wild, Ethiopian pig. I had it on a black leather belt. It's not shiny because...well, read on.

Not long after we arrived in Winchester the other week, the bar attaching it to the belt came adrift at one end. This was clearly slightly inadequate soldering on my part, but should have been simple to fix. All I had to do was resolder it, pickle it and polish it up, before reattaching it to the belt.

The key words "pickle it" are where I went wrong. When you solder silver, you have to use flux to make the solder flow properly, and this results in blobs of a glassy slag stuck to the work when you finish. To remove these, you drop the piece into 10% sulphuric acid, which dissolves the slag. It does attack the silver, but much more slowly than it eats away the slag.

For decades, I've used pickle at room temperature, but recently acquired an old filter coffee maker to use instead. After cutting the top off, I now have a perfect pickle container which keeps the acid at about 85°C.

It's common knowledge that when you warm things up, chemical reactions go faster, which was why I started using the coffee maker. If you can get away with a few minutes, why wait half an hour? After soldering the bar, I dropped it into the hot pickle, and at around that moment, Per arrived.

Per was Jenny's first PhD student, many years ago, and is now Professor of Organismal Biology at the University of Uppsala in Sweden. He was visiting Jenny for a few days to work on a project they're collaborating on.

Some 3 hours later, I remembered my buckle in the pickle. As you can see, it is ruined, and not hard to work out why. For each 10°C rise in temperature, everyday chemical reactions go twice as fast. I'd normally leave a piece of silverwork in the pickle for 20 minutes or half an hour, and expect it to come out nice and clean.

At 85°C I calculate the reaction would go 20 times as fast, so a minute or 2 would have been plenty. I gave it 3 hours.

As you can see (especially if you click the image to see it big), the acid has eaten right in places. Severe worm damage! The bar I carefully soldered back on is so thin and flimsy, it's completely useless. The whole buckle is scrap. What a twerp!

Fortunately, I still have the original silicone rubber mould I used. I can make a new wax, and should be able to cast a replacement when we go for our silversmithing weekend in October. Hope so. I was always rather pleased with that buckle. One difference, which might be interesting, is that the place we go now only does sand casting, so the result will be substantially different.

The way I'm used to casting silver is the lost wax process. I usually start with plasticene on a sheet of glass to make the original. Then pour silicone rubber over that to make a mould. Get rid of the plasticene and pour molten wax in to the rubber mould to get a positive. Stick the wax in a steel cylinder and pour investment (a bit like plaster of paris, but heat-resistant) around that. Melt out the wax in an oven (hence "lost wax"), then pour molten silver into the space previously occupied by the wax. Break away the investment and there is your raw silver casting, waiting to be finished. Although there are many stages, they're all pretty simple, and you can get brilliant detail in your casting.

Although the sand used for sand casting is pretty fine-grained, it's still much coarser than the investment, so inevitably the end result will be rather different. Might still be perfectly fine. We shall see.

Oh yes, must not forget. There will be more silence. Sorry. All will become clear in due course.

Friday, 5 September 2008

A funny old week

Maybe it's just post-holiday depression, but it's been a funny old week; vaguely dissatisfying; the sort of week where you can't quite settle down at work, despite having rather a lot to do. Bitty, is how it's been, with work review and planning meetings, which are always induce a loss of the will to live.

Monday we did some serious note-bashing with part of the choir, since Jenny and I can only make one more rehearsal before the concert at the end of the month. Wednesday we went to a local Thai restaurant with a bunch of folks, and ate very satisfactorily. And tonight Jane is back from a week's holiday so we're feeding her and Lorna and Richard Rose Gray and Ruth Rogers' Penne with Aubergine, which is a very self-indulgent mix of aubergine, tomatoes, mozarella, parmesan and penne. And just the thing for the end of this sort of a week. No doubt accompanied by large quantities of red wine, I need hardly add!

I did notice this morning two little black and white heads poking out of the second martin's nest, so it looks as though they'll be fledging any day now, and not a moment too soon, as they'll have to build their muscles up before flying off to South Africa, or wherever it is they go. It is particularly satisfying to be able to report that the first time we actually had martins nest on our house, they produced 2 broods.

And now I must go and assemble the shopping list, or we'll not have it all ready when the hordes arrive. I'll leave you with this , behind which lurks a 3Mb jpeg of the Alice Kettle tapistry I raved about a few days ago. I spent some time with Photoshop, squaring up the photos and then stitching them together. Sadly, I'm crap at Photoshop, so you can see the joins only to well. I did have a go at making the joins less obvious, but I think I only made it worse. The line down the middle is particularly bad, as I think there really was a tiny bit of the tapestry missing from my snaps. Think of it as an impressionist photo, rather a 100% accurate representation.

Oh! Bloody Blogger has swapped the colours about. All that blue is actually red. Wonder how that happened!

Edit: Other people's pictures are available here, or scroll down this one a bit for a view from outside the Discovery Centre.
Alice Kettle's own website is here.

Monday, 1 September 2008

Winchester Choir Week

So the reason for the week's silence is that I've been in Winchester with the choir, singing the evening services in the Cathedral. If you're interested, the programme is here.

We've been doing this for over 10 years now, but Winchester Cathedral is one of my favourite buildings in which to sing. We actually did Choral Evensong each evening at 5.30 with Wednesday off, and Mattins, Eucharist and Evensong on Sunday. With a good 3 hours rehearsal each day, it's quite tiring, but we absolutely love it.

The drive down was easy and fast, but as we approached our destination, I remembered I'd not packed my black shoes (the men wear dark suits), so the first thing to do after lunch was to buy some. Of course, with only half an hour to locate and purchase said items, I made a bad choice and the result was sore feet during all the services for the rest of the week. I'll have to get them stretched.

High points were Monday's Purcell Magnificat and Nunc Dimitis, and Tuesday's Lord, let me know mine end by Maurice Green. Both fabulous pieces which we did rather well. Sadly, the week was marred by some really grim singing in the Mattins, particularly the psalm, which went badly wrong. And for no obvious reason. We're good at psalms, and people comment on the fact that they can hear the words. But my goodness, the Mattins psalm was dire. Fortunately, it was also very short!

We stayed in Sparsholt Agricultural College just outside Winchester, sleeping in student accommodation which was a lot more comfy than I remember from my uni days. The food in the refectory was very acceptable, too. For those who listen to BBC Radio 4's Gardeners' Question Time, the GQT Potting Shed is located in the grounds here.

But best of all was the eating out. In Sparsholt village is an excellent pub called the Plough, where you get wonderful food and where they have a pretty good wine list, too. And it's within walking distance of the college. We had lunch there twice. First time I had a smoked pigeon and bacon salad; second time was slow roasted belly of pork which was gorgeous and at least twice as much as I needed.

In Winchester itself, we ate lunch twice in the Old Vine, which faces onto the Cathedral Close. Fried chorizo with patatas bravas and a chilli dip. So good, I had it both times!

Actually, I say the food was the best, but really, the company was the best. What a pleasure to be able to spend an extended period doing something you love in the company of some really good friends. Two of the choir were among the previous Saturday's dinner party guests, and at one point I had my four favourite women in the car with me! Oh yes, very good indeed!

The drive home yesterday was less good. Jane had very kindly driven us home in my car after the choir dinner on Wednesday (so I could drink), but the tiddly roads give little opportunity to give the car any welly, particularly at night, so I offered to let her drive us home from Winchester to Royston, thinking that the motorways would allow her to floor the throttle and see what the car would do.

Sadly, not only was the weather completely foul, with lots of really heavy rain and standing water on the road, but the traffic was heavy, and there had been a crash on the M25 which had damaged the road surface. Two lanes were closed, and for mile after mile we just crawled along. A drive which had taken an hour and three quarters on the way down took four and a half on the way back. Gruesome. Poor old Jane took it in good spirit, but I'll have to find another opportunity to let her play!

So I leave you with some phone snaps of a spectacular tapestry by Alice Kettle, which we saw in the Library. We are complete ignoramuses about tapestry, but apparently Alice Kettle is the artiste du jour. The tapestry was fabulous. My efforts do not remotely do it justice. They start at the left hand end and work to the right.