Tuesday, 17 June 2014

In praise of metal detecting. 2. Conservation

Farmer plowing in Fahrenwalde,
 Mecklenburg-Vorpommern, Germany

photo: Ralf Roletschek

A sight rarely seen today, the horse-drawn plow and
other earlier agricultural practices which are
impracticable today had far less impact on the land
than the heavy machinery and monocultures of our
Henry Mossop's passion for conservation and his interest in metal detecting are thoroughly interwoven. Today, detectorists on agricultural land see diminishing returns in the same fields year after year. This is not simply that they are exhausting the finds, but what they do find becomes ever more fragmented and corroded as time passes. Some archaeologists, pedantic in their views and unable to experience systems are heavily critical of the activity. Others of more modern (but not modernist) intellect seek ways of aligning their interests with that of the metal-detecting hobby. The Portable Antiquities Scheme is the best example of this attention and it has been noticed that criticism of metal detecting is the one of main reasons that finds are not reported. People are basically good and like to contribute to worthwhile activities. That attitude, however, quickly becomes soured in the presence of hostility.

When people become enmeshed in organizations, their individuality is lessened and it can be seen (by others) that their awareness of other points of view and the very nature of the individual is also lessened. The dyed-in-the-wool bureaucrat is the classical example of this outlook and it was a favorite topic of writers like Kafka and Orwell. It came as only a slight surprise to me to hear, many years ago on CBC's award-winning science program Quirks and Quarks, that no important discovery in science had ever been made by anyone funded to do such. An American philanthropist, whose name escapes me, sought to rectify this situation by giving money to independent researchers solely on the basis of their passion and not on any foreseeable practical application. Good research follows its own whims and cannot be defined at its outset. One cannot say if a particular application will take two days, twenty years, or beyond the lifetime of the researcher. It does not matter, it is not the destination that is important to the researcher, but the journey. I was reminded, today, of a favorite saying of Captain Sir Richard Francis Burton: "Needs must when the devil drives" and I find it interesting that its definition is widely misunderstood.

A patina finds equilibrium between its internal matter and its external environment. Nature finds harmonics even in human behavior and this is expressed in the previous paragraph about the inability of many to see outside of their own frame of reference. A good researcher is an outsider, and it is his or her's task (in order to be successful) to develop that patina between themselves and their society just as it is societies task to develop its own patina to their presence also. No one has ever been remembered as a successful follower, but the label of boot-licker will at least take them to the grave.

Even since the adoption of the tractor, agricultural machinery has been getting much heavier and this has resulted in speedier soil compaction. A hard layer will form in the earth where water will not drain easily. Any ancient metal objects above this layer will thus lose the equilibrium of the patina built up after hundreds or thousands of years. As this build-up of moisture increases, the farmer will try different approaches to the problem: seeking ways to drain the land or break up the hard layer, itself through deep plowing or subsoiling. The patina will then be attacked and will, again, seek equilibrium with its new environment. However, it cannot possibly catch up to the farmer's actions and the corrosion becomes an ongoing, live process, until nothing remains of the metal but a stain in the ground. I have seen Roman coins become nothing more than corrosion products after being exposed on the surface. Sometimes. an image of the original coin remains but any attempt to clean it results in nothing at all remaining.

Many agencies change the position and status of objects in the ground, it is not just agricultural equipment, but worms, ants, rabbits, and various sorts of erosion. All of these create new environments where metals seek new equilibrium. About the most famous example is the Sutton Hoo burial where rabbits had changed the very proportions of the mound and the position of the grave goods was not obvious.

Once an object gets closer to the surface, the plow blades can break it up further. Silver and copper alloys can become crystalline and brittle over the centuries. If you drop an ancient silver coin on a hard surface it can even break in two (this once happened with an extremely valuable ancient Greek dekadrachm!).

If all of this was not bad enough, the actions of fertilizers and pesticides also destroy the equilibrium between the interior of an object and its environment. A British metal detectorist told me that he had observed this process to be far slower on organic farms. Also, in certain environments, freeze and thaw cycles can also attack the integrity of the object once it gets to within five to three inches of the surface. I have seen this crazing on the more porous fossil remains in the Alberta Badlands. It only takes the impact of a foot or hoof or sliding rock to turn it all into loose fragments. Monoculture and the absence of allowing fields to fallow adds to the problem.

Thus, the detectorist automatically becomes an environmentalist and conservator by their very actions. The idea that the archaeologists will eventually save everything, and do this faster than nature can destroy it is an absurdity and we must wonder about the mental state of those who would make such claims. Is it a knowing lie, or something akin to functionaries disease?

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  1. John thank you again. I have been a detectorist for close to 40 years and the attempts by a few to shut down our pastime is forever ongoing. The idea that they will eventually have the time and the money (ours) to recover all that lies beneath the soil amazes me. I suspect we are easier to beat up than the shopping center developers or road crews.

    1. You are most welcome, Dick. You also have anticipated tomorrow's subject with your comment about shopping center developers and road crews -- I have some actual figures that will show how archaeologists trying to stop detectorists is a bit like a flea trying to claim ownership of the dog!