Mokka mit Schlag

A quick proof of something that bothered me in basic topology. Assume the standard topology on ℝⁿ based on open balls. What about an open box? I.e. all points in ℝⁿ such that a₁ < x₁ < b₁; a₂ < x₂ < b₂;…;a_n < x_n < b_n. Is this an open set? I.e. can you build it up out of a union of open balls? Or, more colloquially, can you pack a square hole with round pegs without leaving any gaps?

Short answer: yes, if the balls can overlap and you have infinitely many of them. Long answer:
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I’ve gotten completely addicted to eBooks this year. I now have a library of hundreds of ePubs and PDFs covering almost every category in the Dewey Decimal System. However I’m finding the available eReading software weak and inadequate for a lot of uses. The best I’ve found so far is Aldiko Premium ($4.99 at the Android App Store) combined with the open source Calibre on my desktop and laptop; but I want better. In particular here’s what I find missing in current options:
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My wife and I picked Bermuda for our July 4th vacation because it was reasonably close, had nice weather, spoke English, and we’d never been there. Oh, yes, it only had one possible life bird for me to find so I wouldn’t spend the entire trip looking for birds instead of sightseeing with her.

That bird is the White-tailed Tropicbird, locally known as the Longtail. The Bermuda Petrel or Cahow is out at sea at this time of year. However the White-tailed Tropicbird is common. You can also see these from East Coast pelagics in the United States, sometimes even from New York shores if there’s a hurricane; but they’re far easier to find here. They’re like looking for Laughing Gulls at Coney Island.

I’m reasonably sure I saw some from the cab from the airport, but I couldn’t be quite certain. However as we had lunch on the hotel veranda while waiting to check into our room, several definitive White-tailed Tropicbirds flew along the ocean parallel to the beach. #847! Now we can see sight-see at a leisurely pace for the rest of the trip. :-)
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Usually rare birds for an area are just vagrants, but this summer a pair of Mississippi Kites actually built a nest and started breeding in Sterling Forest! Growing up in Louisiana you’d think I’d already have Mississippi Kite on my life list, but I guess I wasn’t paying that much attention to birds back then. So Janet, Monica, Sandi, and I stopped at Sterling Forest on our way up to the Adirondack Birding Festival on Thursday to try to find them. Unfortunately we were too late. They were seen earlier that morning but after a bad traffic jam in the Bronx we didn’t get there until around 11:00. :-( I suppose we could have stayed till the late afternoon when they usually return to the nest, but we had a long drive still ahead of us to Hamilton County.

We returned to the Sterling Forest parking lot on Sunday afternoon on our way back from the festival. Still no Kites. damn. However just as it was starting to rain again and we were getting ready to give up we ran into another birder who told us the kites were indeed still there and visible from a spot just down the road. So we trotted on down and there they were, both of them:

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The birding trip for Saturday afternoon was to a couple of areas on either side of Indian Lake. They had some great insects, but not too many birds. Afternoon is not generally the best time to see birds. Too hot, and many birds are resting. However toward dusk we made a final stop at a marsh on the south side of Indian Lake. I mostly stayed by the car and the road, looking at spiders and turtles, while the rest of my carpool explored the surrounding area hoping to pick up a woodpecker or two. They should have stayed by the car too. While they were off in the swamp, a Black-Backed Woodpecker flew into a dead tree, called once or twice, and then flew off. #845 and third life bird of the trip for me.

Don’t feel too bad for the other members of my party though. They all got Black-Backed Woodpecker the next day at Northville-Placid Trail too. In fact we had several there.