Thursday, December 27, 2007

Western Astrolabes

My husband, who I love, gave me Western Astrolabes by Roderick and Marjorie Webster for Christmas. Its part of the Historic Scientific Instruments of the Adler Planetarium and Astronomy Museum. It says astrolabes, but it covers quadrants and mariner's astrolabes as well. It's split into 5 parts.

The Introduction: A Cross Cultural and Social Perspective gave a fair introduction to the overall development. There are very nice redrawn illustrations from (I think) woodcuts that are going to to useful in future classes, especially if I teach one on surveying. There are also illustrations on how to use it to aid in architectural drawings. The text leaves something to be desired, though. I disagree with their weak assertion that astrolabes were used for astrology and not much else. They mention Levi ben Gerson and Walcher, both of whom used the astrolabe for observations, but then swing into Brahe's denunciation of it as too crude an instrument for his use. It's like saying observations taken with McDonald's 36" telescope aren't valid because the 105" is next door. So? The 105" is better for some things, but the 36" can still be used to do some darned fine science. Just because something was inadequate at the end of the 16th C doesn't mean it wasn't extremely useful earlier.

The next section is a technical introduction. When they say introduction, they mean it, but I think that's probably fair because they wrote an earlier book* that probably covered all that. I'm on a search for it now. The problem with most astrolabe books (IMO) is they assume 20th century knowledge and drawing instruments. I want to know how they did it in period! I'm working on getting together a web site to detail this now, but reading medieval latin gives me a headache. I'm looking for the right translations, but I haven't found them yet. I can put something together from Vitruvius, but I'd like something later, please.

The third section describes the astrolabes. It's lovely, although not as detailed as Epact. They give tables(!) of the info found on each instrument they describe, which is going to help with my compilation of period bright star names and symbols. The text descriptions give enough info to tell what you're looking at, but not enough to recreate it. I suspect Dirty Rotten Kitty will be having his way with Chicago next summer. Kenna wants to go there to look at leaky old Frank Lloyd Wright houses anyway. We'll have to confiscate the BB gun before DRK sees all those windows, though.

The Quadrant section is skimpy and mostly post period, but quadrants are pretty straight forward, so I can't complain.

The Mariner Astrolabe section is short- 2 post period instruments.

The Appendices are nice- a catalog of stars found on the instruments and a lovely bibliography.

It was a good book, but if I had to have just one, I think I might go for Scientific Instruments in Elizabethan England. That's all early 16th C to early 17th C, but there's enough discussion to let me trace back some. Epact is still my favorite place. It seems like I have to reach some of the most interesting info from cached pages, but OMG does it have info on there. I'm holding out high hopes for the History and Practice of Ancient Astronomy by James Evans, which my parents got me this Christmas. And I *really* want to go to Adler now and scrawl notes all over my nice shiny Christmas present.

If anyone is interested, this is the astolabe kit you want. Or email me and I'll send you a PDF of my paper Chaucer kit, but the only plate at the moment is for Portsmouth, Ohio.

* 1.Title: Astrolabe Kit and the Astrolabe: Some Notes on Its History, Construction and Use (Review)
Author(s): J. L. Berggren
Author(s) of Work: Roderick S. Webster
Source: Technology and Culture, Vol. 18, No. 1. (Jan., 1977), pp. 151-153.
Stable URL: http://links.jstor.org/sici?sici=0040-165X%28197701%2918%3A1%3C151%3AAKATAS%3E2.0.CO%3B2-Q

Flying Monkey Minions

(This is an early mug shot)

I started this blog to keep track of my astrolabe research, so of course my first post will have nothing to do with that.

Dirty Rotten kitty is a member of the family and travels with us wherever we go- mostly because the FBI wants him under close supervision at all times. He's sold the Grand Canyon to BFI for waste disposal, harassed the sprites at Taliesin West, hijacked the USS Salem, incited a counter-revolution at Fanuiel Hall, upgraded the descriptions in the Museum of Natural History, put up an exit sign over the back door of the Alamo.... You get the picture.

I was ignoring work at thinkgeek.com before Christmas and found the screaming monkey slingshots. I *knew* I had to give one of these things to someone I loved. But if I gave one to Kenna, Caitlin would pout and if I gave one to Caitlin, Kenna would liberate it. So I bought 2 to keep the violence to a minimum on Christmas morning.


Unfortunately, I got the monkeys smuggled into the house on Christmas Eve, planning on hanging them from the angel on top of the tree, but the monkeys had other ideas. Once they found out they were entering the lair of Dirty Rotten Kitty, they immediately swore fealty to him. You know how flying monkeys are- once they swear fealty, that's it. So I found an old sweat sock, stuffed the monkeys into it, hung it with the other stockings and waited for Christmas morning.
Dirty Rotten Kitty was thrilled with his new flying monkey minions. It was what he'd always wanted, next to explosives and fissile material, of course. The monkeys are all excited- every time I sat down on Christmas Day, they mysteriously launched themselves toward me, screaming merrily. Now they all live together in the Cat Cave under the monkey reading lamp on Kenna's side of the bed, plotting world domination, forging $1 lottery scratch off tickets and singing along with Mike Oldfield CDs.