Julius Kröhl

Julius Hermann Kröhl (also Kroehl ; * 1820 in Memel ; † September 9, 1867 in San Telmo ) was a German engineer and submarine designer who emigrated to the USA . With the Sub Marine Explorer he built the world's first functional submarine.

Life

The son of the Memel merchant Jacob Kröhl moved to Berlin early on . There he studied engineering. After his military service in the Prussian army, he emigrated to the 1844 United States from. He opened a metalworking workshop in Manhattan . In 1852 he succeeded in building the dome of the New York Glass Palace, a technical masterpiece, as the filigree roof was supported by curved iron girders that were difficult to manufacture at the time. In 1854 he received American citizenship. The following year he got his advanced iron bending machinewith which he could shape the rigid metal. In 1858, he married Sophia Leuber in Washington, DC .

Malaria was stated as the cause of death on the death certificate . Kröhl lies in the Panama City emigrant cemetery .

American Civil War

During the American Civil War , Kröhl served in the Northern Navy. There he was considered a specialist in underwater explosions and also as a scout . At the end of 1861 he was commissioned to end a southern blockade in the Mississippi. He offered the local commander to use small rowing boats to attach explosive charges to the enemy ships at night. This project was rejected. The outgoing convoy was able to break through the blockade, but suffered heavy losses. Kröhl was slightly injured. As a result, the idea of ​​a submersible matured in him, with which one could attach explosives to enemy ships.

Sub Marine Explorer

The wreck of the now completely rusted Sub Marine Explorer on the beach of an island off Panama

In 1863 Kröhl offered his draft of a submarine to the military in the northern states , but they were not interested. Kröhl then faced financial ruin. He was only able to realize his design with the Pacific Pearl Company and built the Sub Marine Explorer in 1865 . In 1866 the first official dive took place in the New York harbor basin . During this demonstration run, the Sub Marine Explorer became the first submarine in the world to reappear on its own. The boat had three pressure locks in the bottom from which pearls could be collected from the seabed. Kröhl envisaged a screw as the drive, which could be operated with muscle power. At the end of 1866, the submarine was dismantled and shipped to Panama . Kröhl was given the job of diving for pearls and mother-of-pearl shells there.

After several diving trips, Kröhl and his team died in September 1867. Malaria was given as the cause of death . However, it can be assumed that they all died of the then unknown diving disease , because the quick ascent after the many dives of up to four hours in more than 40 meters depth was carried out without decompression . The burial was carried out by the local brotherhood of Freemasons in the Cementerio de Extranjeros (Foreign Cemetery ) in Panama City in the Chorrillo district . A portrait of Kröhl has not been preserved.

The submarine is now corroded by rust and cannot be restored in a bay on the island of San Telmo in the Gulf of Panama southeast of Panama City (coordinates: 8 ° 16 ′ 53.7 ″ N, 78 ° 50 ′ 45.2 ″ W ) .

literature

• James P. Delgado: Misadventures of a Civil War Submarine. Iron, Guns, and Pearls . Texas A&M University Press, 2012, ISBN 1-60344-472-6 ( limited preview in Google Book Search).

Web links

• "Rusty monster in front of San Telmo" ; Homepage for the Terra-X broadcast of October 4, 2009
• Diving trips: The curse of the deep , ZDF broadcast TerraX
• The discovery of the Sub Marine Explorer (with a short biography of Kröhl) from Der Spiegel No. 16 from April 15, 2006
• “A legend emerges” ; Article from the "Süddeutsche Zeitung" from June 9, 2005
• "Surfaced" ; Article from the "Welt" from June 9, 2005
• Behalf of the City of New York for a fire observation tower of iron (English)
• Summary of various articles
• 1865: Julius Kroehl's Sub Marine Explorer (PDF; 315 kB)

Individual evidence

1. ↑ U.S. Patent No. 12,133 patent on uspto.gov (Apple Quicktime required for the images)
2. ↑ The Secret of Pearl Island . DER SPIEGEL 3/2006 by Sven Röbel (from May 9, 2006). Retrieved June 17, 2013.
3. ↑ Julius Kröhl - The Forgotten Father of the U-Boats  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.