Sponge diving is

underwater diving Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving (disambiguation), diving, an ambiguous term with several possible meani ...

to collect soft natural

sponge Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...

s for human use. Sponges

Background

Most sponges are too rough for general use due to their structural spicules composed of

calcium carbonate Calcium carbonate is a chemical compound with the chemical formula . It is a common substance found in Rock (geology), rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skel ...

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant f ...

. But two

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

, '' Hippospongia'' and '' Spongia'', have soft, entirely fibrous skeletons. These two genera are most commonly used by humans. It is unknown when exactly the sponge became an article of use. In

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

writings,

Homer Homer (; , ; possibly born ) was an Ancient Greece, Ancient Greek poet who is credited as the author of the ''Iliad'' and the ''Odyssey'', two epic poems that are foundational works of ancient Greek literature. Despite doubts about his autho ...

and

Plato Plato ( ; Greek language, Greek: , ; born BC, died 348/347 BC) was an ancient Greek philosopher of the Classical Greece, Classical period who is considered a foundational thinker in Western philosophy and an innovator of the writte ...

mentioned the sponge as an object used for bathing. Through trading,

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

ans used soft sponges for many purposes including padding for helmets, portable drinking utensils and municipal water filters. Until the invention of synthetic

sponges Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and ar ...

, they were used as cleaning tools, applicators for paints and

ceramic glaze Ceramic glaze, or simply glaze, is a glassy coating on ceramics. It is used for decoration, to ensure the item is impermeable to liquids and to minimize the adherence of pollutants. Glazing renders earthenware impermeable to water, sealing th ...

s, and discreet

contraceptive Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth control only be ...

s. However, by the mid-20th century, over-fishing had brought both the animals and the industry close to extinction. Many objects with sponge-like textures are now made of substances not derived from

porifera Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a Basal (phylogenetics) , basal clade and a sister taxon of the Eumetazoa , diploblasts. They are sessility (motility) , sessile ...

ns. Synthetic "sponges" include: personal and household

cleaning tools Cleaning tools include the following: *Acoustic cleaning * Air blaster * Air knife * Besom * Broom * Brush * Building maintenance unit * Camel-hair brush *Carbon dioxide cleaning * Carpet beater * Carpet sweeper *Chamois leather * Cleret * Cyclone ...

breast implant A breast implant is a prosthesis used to change the size, shape, and contour of a person's breast. In reconstructive plastic surgery, breast implants can be placed to restore a natural looking breast following a mastectomy, to correct congenita ...

s, and contraceptive sponges.

History

In Kalymnos, only 18% of the steep

volcanic A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

land could be cultivated, so the main occupations were trading,

boat building Boat building is the design and construction of boats (instead of the larger ships) — and their on-board systems. This includes at minimum the construction of a hull, with any necessary propulsion, mechanical, navigation, safety and other ser ...

and sponge fishing, which perhaps was the oldest occupation on the island. Diving for sponges brought social and economic development to the island: the

freediving Freediving, free-diving, free diving, breath-hold diving, or skin diving, is a mode of underwater diving that relies on breath-holding until resurfacing rather than the use of breathing apparatus such as scuba gear. Besides the limits of breat ...

method was originally used. Kalymnos was the main centre of sponge production in the Aegean, and sponge diving is still a traditional albeit less common occupation of the Greeks on the island, with related exhibitions, along with other local folklore, and three museums about the occupation. Sponge fishing LCCN2003666909

When sponge diving, the crew went out into the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

in a small boat, and used a cylindrical box with a glass bottom to search the sea floor for sponges. When one was found, a diver went overboard to get it. Freediving, he was usually naked and carried a skandalopetra, a rounded stone tied on a rope to the boat, to take him down to the bottom quickly. The diver then cut the sponge loose from the bottom and put it into a net bag. Depth and bottom time depended on the diver's lung capacity. They often went down about for up to 5 minutes. When the Greek sponge divers started using surface supplied standard diving suits (locally called ''scaphandro'') in 1865 the death and injury rate from

decompression sickness Decompression sickness (DCS; also called divers' disease, the bends, aerobullosis, and caisson disease) is a medical condition caused by dissolved gases emerging from Solution (chemistry), solution as bubbles inside the body tissues during D ...

was extremely high as the procedures for safe decompression were as yet unknown. Some estimates put the death toll at around 10,000 Mediterranean divers in the first 50 years of surface supplied diving. French Navy physician Alfred Le Roy de Mericourt reported that in 1867, the suppliers of the diving suits reported that out of 24 divers using 12 scaphandros, 10 died during the season. By 1868 the Italian doctor Alphonse Gul observed that three divers would share a suit, and of the thirty divers at Kalymnos, two died and two were paralysed that year. The improvement in fatality rate was ascribed to the reduced daily diving time resulting from sharing the suits.

References

External links

* – Blog, but has interesting images and some useful information {{Underwater diving, prodiv Underwater work Commercial diving Kalymnos