Spalling in Progress

Here's a good example of spalling in progress. The brittle cement itself is cracking, top center. The expansion and contraction of the brand new cement is accelerating damage to the stone, bottom center.

The Cement Problem

From John Messina's book about Alamos architecture, which I highly recommend:

"In recent times, Portland cement has been added to the plaster mix in order to make it harder and less likely to wear away. This combination, however, produces a hard and impervious coating that prevents any of the inevitable moisture that has entered the wall from escaping. Water will thus be retained, and the wall will gradually erode from the inside. Unfortunately, many contemporary masons and plasterers working in Alamos have resorted to cement plasters. Thos entities and authorities charges with preservation oversight urgently need to educate the local trades and owners regarding this problem."

First, Wait a Quarter of a Century

The profession of restoration has a very strict code of ethics that reads somewhat like the Hippocratic Oath:

1) First, do no harm.
2) Every step you take should be reversible.
3) Use the original material whenever possible.
4) Document your work thoroughly with before and after photos.

A friend told me today that construction of the church in Alamos was overseen by the Spanish crown, and the construction statutes of the era called for lime to be slaked for at least 25 years.

During the Roman Empire lime for construction was, by law, slaked for 3 years. When I worked on the frescos at St. Mary's College with Mark Balma, we used 200 year old lime from the Vatican lime pits to make the "bianco san giovanni," the white pigment. European builders and fresco painters in general have long understood that the oldest lime is the best, so they used to pass their lime pits from one generation to the next.

Interestingly, the Maya invented a shortcut. They added tree mucilage to the lime. The sugar content accelerated the slaking process, so the lime was ready for use in 2 weeks, rather than 2 years.

The old building tradition in Alamos called for adding the mucilage of a tree from the same family the Maya used.

Collateral Damage and the Baby with the Bathwater...

Dang. My camera isn't good for macro work. It comes out blurry.

Anyway...I woke up this morning and the first thing I saw was this butterfly. Alamos is extrordinary. Just when you think you've seen it all, you see another of nature's little miracles. A few days ago I saw a hummingbird moth, just an inch long. I was convinced it was a baby hummingbird, or a bee hummingbird blown off course...a species only seen in Cuba.

I was sad a few days ago because I woke up, walked outside and saw a hundred butterfies on the ground, flapping thier wings for the last time. Now they look like this:

I remembered that they sprayed for mosquitos the night before. It's a way of preventing dengue fever...a painful and dangerous disease that becomes a local epidemic if the mosquito population gets out of control.

My one year old baby played on the same ground where the butterflies now lay. If the spray was so efficient at killing the butterflies, I wonder how good it is for him. I feel like somebody is taking too many liberties with his life and mine. I mean, Rachael Carson wrote Silent Spring more than 45 years ago, and we still have to deal with this?

Sadder, my son and I were enjoying sitting out in the yard these days, warming up in the sun. He liked to point at the butterflies in flight. What baby wouldn't? It is a great introduction to the many unexpected wonders he can look forward to in life. Now he points to the butterflies on the ground, and he'll eat them if I don't keep an eye on him every second.

There must be a better way to control the mosquito population. That matter is way outside of my field. I bet Stephanie Meyer has some ideas. She has a good imagination.

I've long believed that human imagination is proportional to the number of species in nature. As an artist interested in creativity, I believe nature is by far the most available and the most sophisticated model one could look to. It doesn't matter much if you call it God's creativity or Nature's creativity. It IS. Simply marvel. Any artist who can remotely approach the incredible imagination of nature's wondrous diversity is doing pretty well.

I submit the above paragraph as THE link between biological and cultural diversity....the first principle of a biocultural outlook.

Honeybees are insects. Without them we can not feed even half of the world's six billion people.

So...if it seems silly to mourn insects, ask not for whom the bell tolls. It tolls for thee.

Spalling Again

When four restorers from Straulino Restoration came to work on the interior of the Parroquia de la Purisima Concepcion, they stayed at the Elizabeth Nuzom house. Every day, they woke up in the morning and walked 50 feet to the church...just across the street. As soon as the walked out the door of the Nuzom house, they saw the column in the photo above. The old stone base is repaired with cement, which expands and contracts at a greater rate than the softer stone, eventually damaging the stone. You see it all over town, like this, just a few steps further: Then they crossed the street and came to the beautiful old retaining wall that surrounds the church that was ruined a few years ago by repairs with portland cement. A staircase leads up to the church. In the photo above you can see really clumsy repairs done with cement, which will accelerate the disintegration of the retaining wall.

Walking towards the wall of the church, they saw this each morning:

Note the cement repairs at the bottom of the photo above. That will cause spalling. The exterior restorers are sure to remove the cement. Restorers treat cement like the bubonic plague.Then they came to this, above. These are cement repairs done a few years ago that have already caused spalling.

Sometimes they walked the other way around, and they saw this, a cement repair on the old brick sidewalk, below:

Then they came up this staircase. You can see the aesthetic damage done to the old retaining wall. It will disintegrate sooner too.

Either way they walked, they eventually entered this door, to begin their day of work on the altar:

Note the very ugly and destructive cement repairs to the sides of the door, down low. The exterior restorers will dig them out, I hope.

Not only did the restorers walk in this door each weekday morning for 6 months, they walked into it several times a day after walking back to the Nuzom house to use the restroom, have lunch or a snack, or to use the telephone. Often, when they went back to work, they did the right thing. They annihilated every trace of cement they could find on the altar.

I talked to Noel, the supervisor. I don't think he really had any idea of the potential positive impact an outside expert like he could have on the conservation of heritage in town other than the church. The builders here are quite stubborn, but an expert from Queretaro might convince them. I pointed out the damage to him, and indicated that this sort of thing can be seen all over town. A few days later, he said, you know, Daan, you have a point.