JamesCronen.com

Recently while doing a home renovation project, I found some razor blades in my wall.

I’ve learned since I published that piece that some medicine cabinets in the middle of the 20th century actually had a slit in them, for the express purpose of razor blade disposal. So it’s very likely that these blades were intentionally dropped into the wall, never to be found again. Thanks to my friends Steve and Marie, who each independently grew up in houses with similar medicine cabinets. Without their input I never would have known of such a cabinet!

Also, my friend Satoshi pointed out to me that the Carey’s blades are likely products of the company that is now Carey International, Inc., self-described as “the world’s leading provider of chauffeured transportation.” J. P. Carey was a barber and entrepreneur, and started a barbershop at New York’s Grand Central Station. His business in Grand Central grew such that he offered other services, including a limousine service. It was the limousine service that really took off and is why Carey’s company is still around today.

Thanks for your help, friends!

My wife and I own a very large, rather old house that was built in 1895. More than a century later, the plaster that adorns many of our walls has cracked. The patches that former owners have applied have been poor, and so some of our walls aren’t quite as smooth as we’d like.

And to make it worse, due to some questionable design decisions by the former residents, the walls of the room we want to use as a nursery had a kind of stucco surface. The walls were bumpy, and in some places, almost sharp to the touch. Rather than sand the walls completely, I decided to attempt my first “major” home improvement project — tear down all the plaster and (with the help of some friends) put up drywall in its place.

While tearing down the plaster on the wall opposite the bathroom, I heard a strange jingling sound that was completely uncharacteristic for falling plaster. I dug around with my gloves, and found a razor blade! And I kept going and found more — about twenty razor blades!

The studs in this area had been cut so that a built-in medicine cabinet could be installed. (Making me wonder why the bathroom has the crappy cabinet we’ve been living with for the past five years.) The bathroom likely had that medicine cabinet between the house’s initial construction and when the bathroom was redone (probably in the 1960s or 1970s).

I’m guessing that the join between the floor and the back wall of the medicine cabinet had a slit that could pass thin objects. Like, say, razor blades. And those razor blades ended up in our wall.

EDIT, July 1, 9:03am: It appears that some old medicine cabinets featured a slit that could be used for razor blade disposal!

Most of the blades I found were Gillette blades, but there were a couple Marlin blades and several Carey’s brand blades.

I have nothing on the Carey’s or Marlin blades. All I could find on Marlin was that Marlin Firearms entered the razor blade business in 1936 and quit about a quarter century later (or so says Wikipedia).

EDIT, July 1, 9:03am: Satoshi managed to find some info on the company that likely manufactured the Carey’s blades.

I have managed to date the Gillette blades, using the Gillette date codes and the exhaustive resources of Dr. Razor. Based on the codes, typeface, and patent numbers, it looks like the Gillette blades were manufactured between 1936–1938… more than seventy years ago!

It’s really fun when you can do archaeology in your own home. Even a tiny link to the past such as a razor blade can make you feel so much closer to the generations that came before. It also makes me think about what kind of artifacts we’ll leave behind for those who will occupy our spaces seventy years from now.

As a physics undergraduate, I never opted to take a circuit theory class. That never bothered me when I was a student. But now, as an adult, seeing the Maker movement in full swing, I’m kicking myself that I never got into electronics.

My dear wife got me a soldering iron, an Arduino Duemilanove, and lots of miscellaneous electronics-related supplies last Christmas, to help me fill this gap in my education.

And finally, last night I sat down and in two hours completed my first soldering project: the Adafruit Industries TV-B-Gone v1.1.

The TV-B-Gone is a simple device whose sole job is to turn off television sets. That might not be too useful at home, since you already have a remote for that. But, consider being out at a bar or restaurant or waiting room, trying to talk to friends or read in peace, while the incessant chatter of talking heads drills its way into your skull. (Why no, I’ve never experienced this, why do you ask?) The TV-B-Gone is a godsend.

The TV-B-Gone kit contains four infrared LEDs, driven by a microcontroller that contains the codes for all major brands of television sets. When you press the button, the TV-B-Gone flashes about 50 power-on codes in sequence, one after another. One of them should turn off the television, giving you the peace you deserve.

(Since televisions use the same codes to turn off and turn on a television, the same TV-B-Gone can be used to atone for your crime if you get caught.)

I opened up the kit and went through the parts list, as recommended. All the parts were included (a very important first step). I brought up the soldering instructions and got to work.

After about two hours of work I was finished, and ready to test my creation. I pointed the infrared LEDs into my phone’s camera, and I could see them flicker when I pressed the button. (Digital cameras can see infrared.) Success!

I liked this kit. The instructions were exceptionally clear, with plenty of photos. The printed circuit board was very clearly marked — if you’re soldering this kit, you have to really have your head in the clouds to mount a component in the wrong place. (And if your mind isn’t on your work, should you really be wielding a 700°F metal stick? Didn’t think so.)

The instructions also provided an intermediate step for testing the device half-way through the build. I understand this isn’t possible for some projects, but I liked having a point at which I could stop, take a break, and verify that what I was doing was working.

I have one very tiny complaint; I would have liked a little more of an explanation of why certain components are needed in the circuit. But I understand that this is a kit for beginners, and too much information might prove confusing.

I heartily recommend the Adafruit electronics kits. I’ll be buying one or two more kits for soldering practice before I start working on my own projects. I think I’ll try the Drawdio next, then perhaps the Conway’s Game of Life kit. If you want to buy the TV-B-Gone kit I’ve mentioned, go here.

Hats off to Ladyada (Limor Fried) for creating a fantastic product.

And, dear readers, if I come over to your house and the television spontaneously turns off? It wasn’t me.

On June 21, 2009, at 1:45am EDT, another summer* began. Astronomically speaking, of course.

We learn in middle-school science class that summer isn’t the hottest season because the Earth is nearest the Sun at that time. Actually, the Earth is about as far from the sun as it ever gets at the time of the summer solstice.

What makes summer hot and winter cold, as our junior high teachers informed us, is the angle at which the Sun’s rays strike the Earth. You can get a sense of this by extending your arm out the window of a moving car. If you face your palm in the direction of travel, so that the wind strikes perpendicular to the surface of your palm, you’ll experience a great force! Turn your hand, however, so that the wind hits you at an angle, and the force you’ll experience will decrease as the angle extends further from the perpendicular.

So, by that logic, why isn’t June 21, the day of the summer solstice, the hottest day of the year?

(Any sun-lovers who happen live in upstate New York have been wondering about the answer to this question, as our temperatures haven’t gotten much above 75 all year.)

Water.

Really — water. There’s a great deal of water on this planet. About 70% of the surface of the planet is covered in water. That’s millions of square kilometers.

And water has a very, very special property — it has a very high specific heat capacity. In other words, it takes a lot of heat energy to raise the temperature of water one degree. This is why boiling water for tea or pasta seems to take forever. Metals (like your tea kettle) have a very low heat capacity. They get hot quickly and cool down quickly.

As the summer goes on and June turns into July, heat is stored in the oceans, lakes, and ponds around us. The water continues to heat up as the Sun’s rays beat down. In the evenings, as the air temperature cools to below that of the water temperature, the heat from the warm water is slowly released into the atmosphere.

Because of this effect, the (average) warmest day of the year is sometime around July 22, a full month after the solstice. The reverse effect happens in the wintertime, and the coldest days of the year fall in late January, not December.

You can also see this regionally. The coasts of the United States tend to have more moderate temperatures than the Midwest, thanks to their proximity to the oceans. An extreme example, consider deserts — deserts get very cold at night due to the lack of water.

So if you’re wondering where the heat is, I only ask you to be patient. The solstice has passed, but the warm weather is yet to come.

*In the Earth’s Northern Hemisphere, which I assume throughout this post, since I and about 98.5% of the readership of this blog lives in the Northern Hemisphere. The same logic applies to the Southern Hemisphere, yet in December, not June.

Despite this being an eponymous blog, I don’t really spend a whole lot of time talking about myself. There are, however, a couple things I’d like to bring up that are unabashedly focused on me.

First of all, and most importantly, my wife and I are having a baby! She’s due on July 20. (That date happens to be the fortieth anniversary of the Apollo 11 moon landing. No, we have no plans to name our child Neil or Buzz.) We don’t know the gender, and have asked the doctors and midwives not to tell us. So far the pregnancy has been almost entirely uneventful, a very good thing. We’re very excited to have a child, and more than a little nervous!

I was, however, laid off from my job back in April. I was very fortunate to find a temporary position three weeks later, but this position ends in mid-July (almost the exact date the baby is due). I was planning on taking a month off after the birth anyway, but as of now I don’t have anything lined up to return to when mid-August rolls around.

I’ve spent most of my career as a Java software developer, but have also spent a few years as a physics teacher. If you know of someone who might be hiring a talented individual for one of those two roles, please contact me.

As always, thanks to all of you for reading!