Bath sponge
The spongin skeleton has been used as a bath sponge by representatives of the horn silica sponges since ancient times . This is a meshed structure of horny threads that are surrounded on all sides by the actual soft body of the living animal. Taken fresh from the water, a bath sponge bears just as little resemblance to a commercial bath sponge as does a living person with his skeleton. By kneading, washing out and leaving it in the humid air, the spongy structure of the bath sponge, which is chemically close to the substance of the silk thread , is freed from the cellular elements. In the past, only the common bath sponge ( Spongia officinalis ) and the horse sponge ( Hippospongia equina ) of the Mediterranean were used. Since the middle of the 19th century , the Caribbean species Spongia barbara (English yellow sponge), Spongia graminea (grass sponge and "glove sponge") and Hippospongia lachne (sheepswool sponge) as well as Hippospongia gossypina (velvet sponge) and the reef sponges Spongia pertusa and Spongia tubulifera were added.
Extraction
Towards the end of the 19th century attempts were made to reproduce the bath sponge artificially. This consists in making as many complete bath sponges as one has cut pieces from a living bath sponge by cutting it up, pegging the pieces and sinking them in suitable places in the sea. In the meantime, these experiments carried out by O. Schmidt in the Dalmatian and Quartier waters had to be abandoned because all the wood facilities were destroyed by the tapworm ( Teredo ) and because the Dalmatian coastal inhabitants destroyed and robbed the facilities.
The reproduction of the bath sponge by free larvae developing from eggs is very abundant; Nevertheless, the yield of sponge fishing was steadily decreasing because exploitation began in the first weeks of spring and millions of larvae still contained in the sponge were destroyed. In 1870 , bath sponge was introduced into England by the Mediterranean states for £ 113,000 . Meyers Konversations-Lexikon (1888–1890) describes the practice at that time as follows: “In the Greek Sea and on the Syrian coast, the bathing sponge is obtained by divers from a boat from May to the end of September . They go 18 m deep and last 90 seconds to 3 minutes. On the Dalmatian and Istrian coasts, the inhabitants of the island of Krapanj fish for sponges with four-pronged forks. The sand, which is almost always found in the sponges, is only incorporated into the wholesalers' magazines in order to increase their weight. "
The value of all kinds of bath sponges imported into the German Empire in 1880 was 7,067,000 Mk ; the export to 1,024,000 Mk.
Although the majority of the sponges used today is made of viscose , there is still a demand for natural sponges, which are harvested by divers in the Mediterranean and the Caribbean . The Greek island of Kalymnos, for example, still supplies around 50 tons of natural sponges per year.
qualities
The finest bath sponge comes from the coast of Syria and Asia Minor and from several islands in the archipelago ; The east coast of the Adriatic Sea to Trieste , the African coast from Tunis to Morocco and the Red Sea also provide sponges. İzmir is the main market for the eastern districts and the main market for western Tripoli . In Trieste, Livorno , Genoa , Venice , and Marseilles , the goods are separated even more precisely according to shape, size and delicacy; The regularly round, bowl-shaped or mushroom-shaped hats are most valued; the most delicate Levant sponges are bought almost exclusively for Paris .
The coarse horse sponges mostly come from Cyprus and the African coast.
The Bahama sponges from the West Indies , known since 1841, are dark-colored, loose and of a coarser texture.
Bastard sponges are the names of the hard pieces that do not swell much in water.
The sponges found in our waters are unusable because they crumble when dry.
The finer sponges can be very refined with suitable treatment, but only at the expense of their durability. They are treated with hot soda solution , carefully washed and placed in dilute hydrochloric acid to dissolve the lime ; They are bleached in a solution of hyposulphurous soda ( sodium thiosulphate ) with hydrochloric acid; This makes them very delicate at the same time, but they have to be washed out carefully because the finely divided sulfur , which is deposited when the sodium thiosulphate decomposes, could be harmful to the eyes when used.
The main trading centers for bath sponges were Izmir , Trieste , Venice , Livorno , Tripoli , Marseille and Genoa .
use
In the past, the compressed sponges (Spongiae compressae) were often used in surgery to widen wounds and remove pus. You press fine, cleaned, moist pieces of sponge together by wrapping them sharply with string or push them into small glass tubes and let them dry here.
The wax sponge (press sponge, Spongia cerata) is prepared by dipping cleaned and dry pieces of sponge in melted wax and pressing gently between slightly moistened boards. The burned sponge (sponge charcoal, Spongiae ustae, Carbo Spongiae) made by burning up sponge waste was also used in earlier times for medicinal purposes against goiter ; its active ingredient is most likely iodine , which is now more certainly used in other forms.
The bath sponge is also used to filter water, in the so-called sponge lamps and for upholstery . It is cut as finely as possible with a rotating knife, washed, dried and then softened in diluted glycerine . After the water has evaporated, some glycerine remains in the fibers and keeps them elastic.
Small natural sponges are also used as menstrual hygiene articles. They are inserted into the vagina with a moisturizing effect during the menstrual period in order to collect the menstrual blood there, and when they are fully soaked they are washed out, squeezed out and replaced. Here, too, there is now an alternative foam product that is sold as a soft tampon .
literature
- Georg von Eckhel: The bath sponge in consideration of the way it is obtained, the geographical distribution and local distribution , Österreichischer Lloyd, Triest 1873
- Peter L. Simmonds: The commercial products of the sea or marine contributions to food industry and art , Griffith & Faran, London 1879
Web links
Individual evidence
- ↑ § 1802 of Title 16 (Conservation of Nature) of the US Code. The Glove Sponge ( Spongia cheiris ) listed there is a synonym of S. graminea according to the World Porifera Database .
- ^ FAO Fisheries department: Sponges: World Production and Markets
- ↑ a b bath sponges . In: Merck's Warenlexikon . 3rd ed. 1884 ff., P. 28 f.
- ^ Author collective: Badeschwamm In: Brockhaus Bilder-Conversations-Lexikon , Volume 1, Leipzig, 1837, pp. 167-168. on-line
- ^ Menstrual sponges (instructions) , kulmine.de, accessed on December 30, 2012