%MRC% Hi Alice - I added a couple things - 'hope you don't mind

Pisa Trip:

Henri Moore, the modernist sculptor, once remarked that the Acropolis temple was more beautiful post WW2 bombings than in its more complete prior state. He argued that the incomplete was more striking, fascinating and arresting to the human eye.

This remark came to mind when I first percieved the leaning tower. It really leans. The video, the pistures, the very name of the place does not live up to the actual perception of such a huge architectural mistake. The mistake is comparable to the Athenian ruins in that it defies usual symmetry, stability and reliablity that we are used to in pre-modern architecture. But I think the interest that comes from seeing the LEAN is not simply in consequence to a superficial comparison with contemporaneous architectural trends. The LEAN points directly at human failure. It embodies the chance that we all take when a project is initiated. It is the reason why we hesitate before building something. What if it doesnąt work? What if it fails? What if it LEANS? Bu there is leaning evidence that mistakes dont ruin a building, asymetry is not the end of a monument. Moore considered it an attribute and Pisa glorifies it. I certainly appreciate seeing a huge, un-erased architectural mistake. I hope no engineer ever finds a way to right it, please leave one mistake in the collection of venerated human productions that flagrantly celebrates that fallibilty of the human mind.

APRIL 24th:

The Pendentive.

Pronunciation: pen-'den-tiv Function: noun Etymology: French pendentif, from Latin pendent-, pendens, present participle of pendEre : one of the concave triangular members that supports a dome over a square space.

Or the following illustration:

I liked to call this structure an interior design cover-up. I thought it existed simply to cover gracefully what would be a series of awkward transitions and lingering right corners scattered accross Renaissance Cathedral Architecture. To support my previous impression of pendentives as intellegent ways of avoiding dark, receding corners in unlit churches, they are often covered with a beautiful frescoe of an angel with uplifted exhalting arms. But upon observing the image provided by Myriam Webster Dictionary, it seems that the pendentive also functions as a supporting structure for the dome. It seems that the angel was maybe not just exhalting God, but literally showing what the pendentive does: hold up the dome, and its drum.

I am not sure how the mechanics play out, but it seems that the four pendentives provide a smooth transition for the weight of the dome to transfer onto the four supporting pillars that the pendentives connect to. Without them, the dome would touch the top of the cube of the nave at only the four keystones of the open arches, resulting in an uneven distribution of thrust and large parts of the dome haning awkwardly and unsafely in mid-air. Brunelleschi's dome does not have pendentives becuase its octoganal drum continues straight down to form the basic shape of the central nave part. But many Renaissance churches have this architectural structure inherited from Byzantine domes. Here are some links and a picture for more mechanically correct explanations of the pendentive.

Here is a photo of a pendentive of a church down the Arno from Ponte Vecchio. its was completed in 1698 by Antonio Maria Ferri. (Its very big, sorry.) * Chiesa di San Frediano in Cestello Pendentive:

Bronze restoration

(See attached Word document at bottom for final writeup with comments from -mrc).

Wax patina research some sites include info. on casting for others in the Bronze Group.


Applying the Patina

The final stage of the process involves applying the patina or coloration to the surface of the bronze. Since bronze alloys consist mainly of copper, sculptors usually apply chemicals to the surface of the bronze to cause a controlled chemical reaction that produces beautiful colors that will prevent corrosion if the bronzes are kept inside. Outdoor patinas need to be washed and waxed each year and eventually will need to be redone.


Patina A patina is a chemical coating that adds a colorful finish to metal sculpture. This is a particularly effective treatment for bronze, which can be given a wide variety of attractive green, brown, blue, and black patinas. Natural patinas, like the creative element of fine art, have a degree of serendipity. That is probably why artists and collectors for 500 years have cherished works of art with rich and deep patinas that developed over time. Art consultants may not be able to predict with exactness the rate which natural patinas develop but they can be knowledgeable about the factors that contribute to change: atmosphere, temperature and humidity.



Random Page mentioning names of different styles of patina: http://lsv.ceramics.org/scripts/wa.exe?A2=ind0204e&L=clayart&F=&S=&P=6933

%MRC% --- cool stuff Alice I found a couple of other links that I had used earlier regarding copper corrosion:

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