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Posts from — July 2008

MPOD hiccups

The companion site to this blog, the Matthew Picture of the Day, has been having a bit of trouble lately. Or rather, the automatic picture-posting program that runs in the morning fouled up on Sunday. I’m not sure why, and I think it was an anomalous, one-time problem. It wasn’t until the afternoon that I realized the problem and manually posted the picture. But the way the picture-a-day software works–checking to make sure it’s been at least 23 hours since the last post–the automation was disrupted, and today’s picture didn’t get posted until the evening either. I’ll manually post tomorrow’s picture, hopefully early, and by Thursday it should be running normally again.

To anyone who thought there wasn’t a picture Sunday or Tuesday: yes there was, and sorry it’s so late.

July 29, 2008   No Comments

A bit of joy

Perhaps you all have seen this:

I came across it via a 3 quarks daily item referencing a New York Times article. That I discovered this two-week old clip–which already has millions of views–so circuitously speaks to the fact that I’m just not up on what’s hot on the Internets these days. 

Any number of descriptors come to mind for this video: goofy, joyful, callow, spontaneous, kitschy, universalistic. One could ask what sort of manipulation is going on when upbeat music makes you feel upbeat. One could find any number of reasons to by cynically dismissive of the whole thing–perhaps by counting up the ways it could illustrate Stuff White People Like. That might have been my reaction, some years ago.

But watching the video did bring me a few minutes of joy today. Upon reflection, it brought to mind the “Dancing in the Street” pattern (#63) from A Pattern Language:

All over the earth, people once danced in the streets; in theater, song, and natural speech, “dancing in the street” is an image of supreme joy. Many cultures still have some version of this activity… 

But in those parts of the world that have become “modern” and technically sophisticated, this experience has died. Communities are fragmented; people are uncomfortable in the streets, afraid with one another; not many people play the right kind of music; people are embarrassed….

The embarrassment and the alienation are recent developments, blocking a more basic need. And as we get in touch with these needs, things start to happen. People remember how to dance; everyone takes up an instrument; many hundreds form little bands.

APL goes on to with recommendations for building an environment that fosters dancing in the street. So however accidentally and undeliberately he got into it, Matt Harding is onto something.

The video clip above is the third of his videos. The second video, from 2006, is similar, but consists mostly of Matt dancing by himself. In fact, it was the spontaneous participation of the children in Rwanda that led, in part, to the idea for the third video. The second video is set to a song called “Sweet Lullaby,” by Deep Forest. Watching the video, the song struck me as quite familiar. Was it from an ad? From This American Life? I was having the hardest time placing it, until I realized that it was actually a track on a Lullaby CD of ours.

July 8, 2008   2 Comments

Iced tea

I like to make iced tea during the summer months. Not that vile powdered stuff, but real tea or herbal infusions. To make it quickly–so one doesn’t have to wait for near-boiling tea to cool all the way down to an icy-cold temperature, I prefer to brew double-strength tea and pour it over ice, such that most of the ice melts, and the near-boiling tea cools, together making an appropriately strong chilled drink.

How much ice does one need? Well, to cool 1 gram of boiling water down to the freezing point, 100 calories1 have to be extracted from it. Melting 1 gram of ice takes about 80 calories of heat. So a mixture of 56% (by weight) ice and 44% boiling tea will melt all the ice and leave the final mixture at 32°F.

How do you measure this amount of ice? Well, you could weigh it, but that’s not always convenient. Here’s a bit of mathematics to justify a simple approximation: The density of ice is approximately 92% that of liquid water. If you fill a container with ice cubes–or with any solid particles, for that matter–there is a fair amount of air space between the grains. If ice cubes were spherical, then only about 64% of the volume would be ice, and the rest air–this is known as the random close-packed fraction. Ice cubes aren’t spheres, but the fraction should be roughly the same. Which means that if you fill a container up with ice cubes, they would melt to a volume about 59% of that of the container. If you add 50% of the volume of the container of boiling water, the ice would represent about 54% of the total mass of water and ice, and mixing the two together you’d end up with a volume of liquid equal to 109% the volume of the container, at 32°F. To avoid overflow, you’d need to use slightly less ice and boiling water.

So, my iced-tea algorithm:


  1. Fill a container most of the way up with ice cubes
  2. Measure out as much tea as you need for the full volume of the container
  3. Brew the tea using a volume of water that’s slightly less than half that of the volume of the container
  4. Pour the brewed double-strength tea (through a strainer, if necessary) into the ice-filled container
  5. Stir to cool the tea and melt the ice; most of the ice will melt. Since the brewed tea will have cooled off a bit while steeping, it won’t have enough heat to melt all the ice and so there will still be some ice left.


The tea leaves will absorb some of the water, and many containers hold (slightly) more than their nominal volume, so using (say) exactly 1 quart of water to make tea in a 2-quart container shouldn’t present any problems.

To brew, I’ve adopted the Cook’s Illustrated technique of mixing the tea and cold water in a saucepan, heating over medium heat to 190°F, then shutting off the heat to let steep for 3 or so more minutes: all total, the brewing should take about 15 minutes.

I’m fond of a mint infusion: for a 2 quart container, use 2 Tablespoons dried mint. I also like minted iced tea, for which I use a mixture of 4 teaspoons loose tea plus 3 teaspoons mint for a 2 quart container.

  1. Thermodynamic calories, not food Calories. A food Calories, spelled with a capital C, is 1000 thermodynamic calories. []

July 2, 2008   2 Comments