Water-flotation
In search of the remains of plants and animals
The conventional collection of finds by hand during the excavation usually focuses only on those finds that are large and distinct enough to be seen by eye during digging. Smaller, less distinctive remains, such as seeds, charcoal, small bones and other bio-archaeological remains are in most cases left unnoticed. These can be collected by employing a special field technique, called water-flotation.
Here the soil sample is washed. B. Wells
Water-flotation is the washing of soil samples that have been collected during the excavation. The specially modified barrel is connected to a water-source and it permits the separation and flotation of all light materials. A set of sieves catch the overflowing materials, thus permitting the collection of remains as small as 250μ (¼ of a millimeter). The process results in the preparation of three fractions of materials, the residue, the coarse flot and the fine flot, each of which may contain a variety of small organic and inorganic finds.
A. The overflow from the barrel empties into the two sieves. D. Mylona. B. The coarse and fine flots from the two sieves have to be sorted under a microscope while the residue (on the right) can be sorted without one. B. Wells.
The most commonly occurring finds are the charcoal, the carbonized and mineralized seeds, the snails and the sea-shells, the remains of sea-urchins, crabs and lobsters, the bones of small animals such as fish, birds, small mammals, snakes and lizards, as well as the smallest bones of larger animals. Additionally, water-flotation produces a range of small inorganic finds, such as coins, beads, pieces of metal and metal rust, chipped stone micro-tools etc.
Some of the animal remains found at Kalaureia: egg shells, snake bones, sea shells.
Many of the remains collected by water flotation are the unique witnesses of a range of past activities. These minute, often humble-looking remains are often very informative on what people used to eat in the past, on the way they cooked and arranged their meals and on the way they disposed of their garbage. They are also informative on issues related to agriculture and animal husbandry, on fishing and on gathering of wild foods, and other raw materials and on the nature and development of the physical world around a settlement. Water flotation has been an integral part of the excavation at the Sanctuary of Poseidon on Kalaureia, resulting in some of the most illuminating finds.
DM
