Concept

I decided to have a bit of fun interpreting this task.

The phrase "leave a message" has two common uses: the "world, hear this!" sense, and the "Susan can't come to the phone right now" sense.

The first is the more obvious choice for this task, and it leads to some exciting possibilities. I'm certainly not above scrawling "buy more stuff" or "unionized service employees average 36% higher pay than their non-union counterparts" in the parking lot of a new chain store; however, it has been done before, and one has to choose between placing it where no one will ever see it and accepting that it will be erased within hours.

So, I decided to do something a little different, by interpreting "leave a message" in the second sense. What if, instead of serendipitously finding wet cement and using it to make a statement to the world, one created a slab of cement solely in order to jot down a telephone message on it? Sounds silly enough to be worth doing. Let's call it, Pavement is Post-It.

I briefly considered bringing the materials to work and waiting until I was given a genuine telephone message for a colleague. But, mixing cement is messy business, and only a hand full of people would ever see the finished product.

Instead, I opted to place a very specific and personal fake message in cement and leave it in public. I pieced together a message likely to bring a smile to regular This American Life listeners, fans of The Books, and students who lived in the Columbia dorms in the early 90s.

(Failed) first attempt

I've never handled cement before. After a few minutes with google, I had a plan. I headed off to the hardware store for 30 pounds of concrete mix, and found an old extra-sturdy cardboard box to use as a form.

I got home, ripped open the bag, and knew I was in for trouble. Instead of the fine sand and cement I was expecting, the aggregate in this stuff was 5mm diameter gravel. There was no way I could hope to write a message with enough resolution to fit any meaningful content on a 2 foot slab.

But, I had nothing else to do with 30 pounds of concrete mix, so I decided to forge ahead. I mixed up about a third of the material. It was much too dry, and wouldn't even clump together, much less allow for lettering. I mixed up the next third, and once again came up with something too try to be useful. So, I went a bit overboard with the water when mixing the final batch. Throwing it all together and kneading it up, I wound up with a wet, soupy goo. No hope of writing on it - I didn't have time to dot an i before the material had slumped to fill in the stroke.

I waited around for a few hours, checking it every ten minutes or to. The consistency never improved - it went straight from too wet to write on to a semi-rigid, crumbly mess with a wet scummy surface. What's more, the cardboard absorbed water from the mix and bent out of shape.

I've now got a 30 pound irregular cement brick. I'm determined to use it in an SF0 task somehow - suggestions are welcome. (I suppose I could take it to the steps of city hall, but I expect dropping this thing off at city hall would turn into a SFPD bomb squad training exercise and leave me trying to explain SF0 to federal agents.)

Second attempt

Never one to give up in the face of obvious incompetence, I decided to try again.

I found some scrap wood and threw together a two by one foot frame, added some scrap hardware cloth for structural support, and I picked up a 10 pound bag of mortar mix.

Everything worked perfectly. The mortar mix includes a very fine sand, and I was able to get lovely modeling-clay consistency. It's actually rather nice stuff to work with, and for twenty cents a pound in small quantities, makes for a really cheap medium.

I poured it into the form, touched up the surface with some scrap wood and a kitchen sponge, and went to work carving my message with wooden sticks.

Installation.

After two days, the thing was dry. I decided not to bother removing the wooden form, since I was never going to use it again and the wood would make the piece a little more robust. After chipping off a few stray chunks of material and sweeping off all the loose bits, it looks pretty good.

I took the message under my arm and set off in search of an installation site. I wanted to place it on dirt near pedestrian traffic. For thematic consistency, I decided placing it near a pay-phone would be ideal. Within a few blocks, I found the perfect spot, placed the work, and took a few photos before quickly walking away.