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The original Daw publishing editions of Michael Moorcock's Elric series.
Just purchased this today:
I have been looking for a decent reference book on spiders for a few years. Found it in a National Park shop where we were walking today.
Spider eye lenses are better than photographic lenses in terms of their image brightness (very low F-numbers). However, because most spider eye retinas have relatively coarse-grained mosaics of receptor cells, their resolution of these images is much poorer than in the human eye.
Search-light eyes
Net-casting spiders (Deinopidae) have eight eyes, but in one genus, Deinopis, two of the rear eyes (PME) are enormously enlarged. Their great, curved lenses face forward like twin search-lights, giving the spiders a rather menacing appearance (the 'ogre-faced spiders').
The two biggest eyes are specialised for providing outstanding low-light night vision. They have enormous lenses that give a wide field of view and gather available light very efficiently. The lenses have an F number of 0.58 which means they can concentrate available light more efficiently than a cat (F 0.9) or an owl (F 1.1). Each night a large area of light sensitive membrane is manufactured within these eyes (and rapidly destroyed again at dawn).
This remarkable combination of large, powerful lenses and the nightly production of new light-sensitive membrane, enables net-casting spiders to accurately track and 'net' their prey at night. Interestingly, they do this without the help of a tapetum, the reflecting layer present in other spiders with highly sensitive indirect eyes.
That sounds incredibly interesting -- any standout references? I once got lost for a couple of weeks thinking about round shields, and even now there's a corner of my brain that's far too full.This weekend I've been reading several academic papers on Bronze Age weapons. Next in line is a book on Warfare in the Old Testament. In particular, I'm looking for the evolution of military technology between the Bronze Age and the Iron Age for a research paper.
You might find Bret Devereaux's blog interesting. He's a military historian, mainly focused on Europe from the Romans through the Middle Ages, but with enough breadth to cover some of the Holy Land conflicts. What he does particularly well is describing how things work. I think his most interesting pieces are multi-part series on how *stuff* was produced, from iron to grain to clothes. He also has some pretty good pieces on siege warfare which might touch on what you're interested in.This weekend I've been reading several academic papers on Bronze Age weapons. Next in line is a book on Warfare in the Old Testament. In particular, I'm looking for the evolution of military technology between the Bronze Age and the Iron Age for a research paper.
Dish washer repair manual.
Try it! It might surprise you.
I just read mine a few weeks ago. 12 year old Bosch dishwasher developed a wash pump issue. Considered doing it myself but the main part was like $300; called in a pro to make sure any ancillary issues would be covered. Usually I do appliance repairs myself.Try it! It might surprise you.
more back issues of Extreme Rocketry
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