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Mr. Merrill is a frequent contributor to THE SUBMARINE REVIEW and is a published author of several books 011 the hist01y of undersea technology. He is a retired engineer with lengthy experience at the New London lab of the Naval Undersea Warefare Ce111er. He currently lives in Wate1ford, CT.

Part 1-The Beginning

Stating with precision the beginning of a technology and identifying the exact time, place and inventor or discoverer is a challenge. The Greeks are credited with developing the first sea mine in the seventh century BC. Sulfur, naphtha, and nitre in a barrel were set afire and placed so as to have the tide or current move the barrel to an enemy vessel and set it on fire. They learned that the weapon, with the aid of a catapult, could be land-based or ship-based.

With the sea mine (sometimes called submarine mine), Dutch roots are found in the l 6’h century” … when the Dutch loaded vessels with large amounts of explosives and sent these drifting mines against an enemy ship or an enemy’s shore fortification.” In 1585, Federico Gianibelli, an Italian working for the Dutch against Spain, sent two bomb ships to drift into a bridge over the River Scheidt at Antwerp, Belgium. The bomb ships exploded against the bridge, tearing a 200-foot gap in it. This was the first time a large explosive charge was used in naval warfare.2 China is credited with using explosive powder for signaling and fireworks in the l01h century. It has been noted that the English may have used the first naval mines in 1627 at the siege of La Rochelle when they launched floating petards unsuccessfully against the French navy. Sea mines evolved through the years from the contributions of many professionals and some amateurs.

In the centuries following the Dutch efforts, gradual acceptance, evolution, and growth of the mine as an underwater weapon took place. An accounting of mine usage at the end of the World War II determined that the Axis and Allied forces laid 500,000 submarine mines. This unique weapon with offensive and defensive capability also does not differentiate between friend and foe. Further, sowing mines and mine sweeping are both considerable challenges. The results obtained with sea mines in World War I and World War II established the mine as a formidable offensive and defensive weapon.

Colonial Period

In 1751, Benjamin Franklin (with his usual prescience) advised regarding how to use electricity to discharge gunpowder but it was not until the Civil War that greater use of electrical detonation applied to sea mines was invoked.

David Bushnell, builder of the one-man submersible TURTLE, is known as the father of mine warfare. Bushnell’s mines with flintlock detonators, adjusted for firing by a light shock, were oaken-staved kegs 14’12 inches in height 13-inches in diameter filled with explosives.

In December of 1777, Bushnell set mines adrift on the Delaware River to be carried by the tide to the target enemy vessels at Philadelphia. However, erratic river currents and intervening ice floes prevented the mines from damaging the enemy vessels. During the Revolution limpet and floating contact mines used against the British ships on the Hudson and Delaware Rivers did not have great success other than deterrence. Mechanically detonated sea mines found their initial place in underwater warfare with these colonial designs. In some quarters sea mines were considered as sneak weapons and not chivalrous.

19th Century-Robert Fulton (1765-1815)

Robert Fulton, famous for his steamboats, was an artist, inventor, submarine advocate and underwater weapon innovator. During thirteen years of fulton ‘s nineteen-year stay ( 1787-1806) in England and France, the two countries were at war. He built and demonstrated sea mines and a submarine (NAUTILUS) with support at various times from both belligerents. Later, when he returned to the United States, his submarine proposal included a steam engine for propulsion.

Fulton’s mine designs included contact explosion, timed explosion, using clock mechanisms to trigger the mine, and mines attached at the end of long spars in close proximity to the enemy vessel. His clockwork mechanism for mine detonation was adjust-able from 4 minutes to 4 hours. Extensive experimentation and modeling were hallmarks of Fulton’ s inventions and their demonstration. On October 15, 1805, Fulton, funded by the Royal Navy, demonstrated a mine’s effectiveness of fWalmer, England. The 200-ton Danish brig DOROTHEA was totaled with the explosion of Fulton’s mine.3 The mine (2 feet long and 12 inches in diameter), filled with 180 pounds of gunpowder and a clockwork mechanism set for an explosion to occur in t 8 minutes, accomplished the complete destruction of the brig. He suggested that in case of war, plantings of 100 anchored mines would be required at the selected sites.

His recommendations to the Royal Navy included blockading British ports with mines to stem potential French intrusion. Fulton also proposed mining the harbors of Plymouth, Portsmouth, Tor Bay and the Thames River. Although he did not meet with complete success in negotiations with the navies of the governments regarding submarines and the use of mines to destroy enemy ships, his ideas were prophetic.

Later, in December 1806, he returned to the United States and promoted sea mines as weapons for the United States Navy. After discussions with Secretary of State James Madison, Secretary of State and Secretary of the Navy Robert M. Smith, he received support and in 1807 successfully blew up a brig in New York Harbor with sea mines but only after several failed attempts. This was due to problems with proper weighting of the mines that caused them to turn over and spill the load of black powder or miss the target.

During the War of 1812, Fulton suggested the moored mine concept that brought the enemy ship to the explosive rather than delivering the explosive to the ship. Fulton quoted a price of $150 per mine, including the powder, to President James Madison. Practical detonation of mines electrically was severely limited at the time due to corrosion of the wires and, significantly, when should they be fired.

The War saw mine-related actions both in the Chesapeake Bay and along the southern shoreline of Connecticut. Some of the mines modeled after Fulton did not succeed in blowing up British ships, but Royal Navy officers assigned to the blockade grasped the significance of mines and their use as a deterrent.

Near New London, Connecticut during the War of 1812, an unsuccessful mine attack on the blockading British man of war Ramilies produced a strong impact. “So great is the alarm and fear on board the Ramilies that Commodore Hardy has withdrawn his force from New London.”

On March 13, 1813, Congress passed an act to encourage the destruction of the armed vessels of war of the enemy. The act, sometimes referred to as the Torpedo Act of 1813, legalized the use of torpedoes as destructive weapons. Fulton’s Torpedo War and Submarine Explosions that he wrote, illustrated, and published in 18 IO raised awareness of the torpedo and led to the Torpedo Act.

Note about Terminology: Generically the word torpedo refers to any explosive charge including the type of weapon now known as the mine. However, Robert Whitehead’s self-propelled underwater weapon inve111ed in 1864 appropriated the name torpedo. Earlier, Robert Fulton experimented with naval mines during the Napoleonic wars and called them torpedoes. In some references, this may cause confusion.

In the latter part of the J 8’h century and the first half of the J 9°’ century extensive effort was directed toward the development and implementation of telegraphy. Telegraphy used wires and delivered an electrical impulse at a distance. An electrical impulse could also be sent along a wire to detonate a mine at a distance. Telegraphy required knowledge to make batteries, wire, wire insulation, and how to make wire waterproof while lying underwater below a river or in the water near a shore. Each of these items has application to mines detonated with an electrical impulse.

During the 19th century, the way was paved for the eventual development of the modem sea mine with the participation of many scientists, inventors, and entrepreneurs. Among those contributing to the related knowledge, experiments, and implementation were Russia, Great Britain, Bavaria, United States, France, Italy, and Prussia. During the century, how to take advantage of underwater mine detonation was a primary pursuit.

Mine Detonation with Electricity Pre-Civil War

Year Scientist Application
1777 Alessandro Volta Pistols, muskets and submarine mines fired electrically
1782 Tiberius Cavallo Gunpowder fired at a great distance by electricity
1812 Pavel L’vovich Schilling In Russia, a mine placed on the Neva River was detonated electrically from the opposite shore
1839 Col. Charles William Pasley Electricity used successfully for submarine gun powder explosion in conjunction with marine salvage
1848 Werner von Siemens field of electrically controlled mines established in the approach to Kiel to deter Danish bombardment of that port during Schleswig-Holstein War. This was the first controlled moored minefield in history, and first installation in time of war. (He was one of the founding members of the Siemens Engineering dynasty)
1854-56 Moritz von Jacobi Russia’s newly-created blockade contact mines (also some shore-controlled detonation mines using chemical action for ignition) were successfully used in the defense of Kronstadt and Sveaborg in the Baltic and Sevastopol in the Black Sea in the Crimean War. The mines provided a major threat to the Royal Navy off Kronstadt.

Other work contributing to the evolution of the mine-related technology during the first half of the 19th century in Europe and United States included that of Bavarian Samuel Thomas Sommerring. In 1812, using wire insulated with India rubber and varnish, he telegraphed through 10,000 feet of cable.

Schilling, a pioneer in defensive mine warfare mentioned above, became aware of Sommerring’s work and used insulated cables and a carbon-arc fuse in the mine’s gunpowder for detonation. One of his demonstrations included the Tsar Alexander I as a witness.8 By 1839, Russia institutionalized mine warfare by establishing a Committee on Underwater Experiments charged to determine the value of mines for harbor defense.

In 1833 in the United States, Robert Hare (1781-1858) (a scientist, professor of chemistry at the University of Pennsylvania, and inventor) reported in the Journal of the Franklin Institute successfully using electricity to detonate gunpowder at a distance of 130 feet. In addition to using this method for rock blasting, he considered this method for exploding mines as a defense weapon for Fort Adams, then being built on the harbor in Newport, Rhode Island.

Fort Adams at Newport was one of dozens under construction and located at strategic waterways both along the coast and inland along rivers and lakes. The work on the forts was well along at this time, and there was significant vested interest in the forts and their role in defense: should exploding moored mines be considered as an assist for the forts or a replacement for them? National level interest In regard to the issue of forts versus sea mines as a means of defending against enemy sea forces seems to have been lacking.

Samuel Colt (1814-1862)

Colt is remembered primarily for his invention of the Colt revolver, the six-shot handgun, and later as a prominent successful mid-191h century New England gun manufacturer. His first United States patent for the revolver was obtained in 1832 when Colt was 18 years old. In the following years, as a result of his efforts to make sales of his revolver to the United States, he became known in Washington from his extensive lobbying for his guns with Congressional personnel. Colt with his broad interest in technical matters was associated with Samuel F. B. Morse, telegraph inventor, in the years leading up to Morse’s epic telegraph demonstration on May 24, 1843. The shared interest was concerned with the burgeoning development and manufacture of insulated cable for telegraphy.

In 1829, Colt, fifteen years old and working for a dye company in Ware, Massachusetts, demonstrated the electrical firing of gunpowder underwater. On July 41h, he posted announcements that he would blow up a raft in Ware Pond. The event took place. The raft was demolished by the blast and onlookers dampened. There is no further record of Colt’s interest in underwater mines until 1836. At that time, the United States severed diplomatic relations with France and President Jackson recommended strengthening the Navy and coast defense. Considering this, Colt configured an extensive moored mine system, Submarine Battery, to protect harbors and other coast locations. The system involved electrical detonation of moored mines, heating the powder to create explosions. The explosion under transiting enemy men-of-war was directed by two visual observers. A full system at a given location would include 2500 mines. With the French diplomatic problem peacefully resolved, Colt’s mine system did not receive attention.

Harbor defense improvement was again brought to Colt’s attention in 1841 when the Maine boundary with New Brunswick dispute with England was ongoing. This time, Colt succeeded in obtaining support. With a $6,000 advance from a $50,000 government appropriation for ordnance development and some private support, he conducted four publicly attended demonstrations of electrical detonation of the gunpowder. Each demonstration achieved its goal; and, in addition. there were vast numbers of spectators and wide press coverage.

The 1842 Webster-Ashburton Treaty resolved the differences with England and removed stimulus for immediate improvement of harbor defenses. Colt’s demonstrations were successful, but the system did not gain favor or acceptance as a weapon. In Washington, there were technical challenges regarding Colt’s basis for a patent that he solicited in 1844. Electrical detonation of mines was reasonably well known by the scientific community both in the United States and abroad. For example, in 1841 the method was used in India to remove a wreck from a river.

Colt’s Demonstrations

Date Location Target Note
4 July 1842 New York Harbor Gunboat Boxer Broad attention lo the concept
20 August 1842 Potomac River Washington, DC Accomac Clam Boat (60 ton schooner) President John Tyler and cabinet attended, 8,000 spectators; control S miles from target
18 October 1842 New York Harbor Brig Volta (260 Ton) 40,000 spcctators
13 April 1844 East Branch Anacostia River, DC Barque Styx 81 ft .. (500 ton) Control 2 miles from target, barque under sail at S knots

In his dealings with Washington, Colt maintained a level of secrecy that caused those in authority to challenge Colt and become suspicious of the system he wished to build. As the operation of a full-born system depended on observers to make the decision to explode the mines, there were challenges as to how the system would perfonn under conditions of fog or at night. Funding stopped and until the Civil War, development of the mine and mine counter-measures10 in the United States were minimal. This curtailment of support for mines has been attributed to Colt’s differences with those in Washington responsible for the development of the country’s ongoing construction of coastal fortifications, the Third System forts.

The large number of spectators at Colt’s four demonstrations and the ensuing newspaper coverage broadened the public’s awareness of sea mines; but with no immediate government support, Colt’s journey into moored mines concluded while his success as a gun inventor and manufacturer continued to grow nationally and internationally. In 1855, Colt had developed the world’s largest annory in Hartford, Connecticut, where his manufacturing tech-niques with interchangeable parts, a production line to increase output, and a positive attitude towards employee welfare enhanced his fame.

Commander Matthew Fontaine Maury (1806-1873)

From August 1825 until April 1861, the Virginian Matthew Fontaine Maury served as an officer of the United States Navy. During the first years of his long naval career, he spent almost nine years at sea mostly in the South Pacific. From 1841 until his resignation to join the newly-formed Confederate States of America, he was Superintendent of the Navy’s Depot of Charts and Instru-ments in Washington (later the U.S. Hydrographic Office). There he attained national and international acclaim for his advances in oceanography and his 1855 book Physical Geography of the Sea. The book, a first on oceanography, was in continuous print for 25 years in the United States and England and was printed in six continental languages.

A few days after the declaration of war, Maury resigned from the U.S. Navy and went to Richmond. His initial role with the Confeder-acy was his appointment by Virginia’s governor, John Letcher, to the Advisory Council on Naval Matters. Maury addressed the Confeder-acy’s challenge of how to enhance harbor and coastal defense with the limited number of Confederate naval vessels available.

One direction of his thinking was to build a large number of small steam vessels with low freeboard (making a difficult target) and heavy firing power. With limited resources for construction, priority was given instead to the building of the ironclad MERRIMACK. The other direction of Maury’s thinking was implementing mines for coastal and river defense. A particular focus of his mine investiga-tion was electrical detonation that he pursued during his brief tenure in Richmond. For the South, controlled mines electrically detonated saw limited use primarily because of lack of reliable waterproof cable suitable for planting

In June, Maury, as a Commander in the Confederate Navy, became Chief of the Naval Bureau of Seacoast, River, and Harbor Defense of the South. With $50,000 allocated for experiments, he focused on developing and implementing mines that floated, drifted or were towed to contact enemy shipping. Some mines were placed on rams on the bows of small torpedo (mine) boats. On July 7, 1861, a little more than two months since Maury’s resignation, he unsuc-cessfully led an expedition to explode torpedoes against the Federal fleet in Hampton Roads.

US Navy Admiral D. D. Porter noted the effectiveness of Confederate mining later in 1878. ” … the difficulty in of capturing Charleston, Savannah, Wilmington, and Mobile, was in a measure owing to the fact that the approaches to these places were filled with various kinds of torpedoes, laid in groups something on the plans of Fulton and Colt, and fired by electricity.”

Of the various mines, the most significant and successful mines were those that were planted and detonated electrically with the aid of an observer. Limited availability of suitable electrical cable impeded broader implementation of this technique. For various reasons such as cost, and material shortages, the contact mine with its low cost and relative ease of manufacture and planting but with some operational limitations, became widely and effectively used by the South.

Torpedo stations were set up in Richmond, Wilmington, Charleston, Savannah, and Mobile. Maury remained with the Bureau until late June of 1862, when he was transferred to England. He did not return to the United States until 1868 and was not on hand to see the effectiveness of the sea mine investigations that he initiated.

Some Confederate Mines

Trip wire
Frame propeller trigger line
Beer-barrel torpedoes
Raft torpedoes with friction fuses
Buoyant torpedoes

After Maury left for England, the Confederate Congress in October of 1862 created a Torpedo Bureau for the Army and the Submarine Battery Service within the Navy’s Office of Ordnance and Hydrography. The Submarine Battery Service mines accounted for sinking at least 40 Union ships. At the battle of Mobile Bay ( 4 August), 1864, a field of 80 mines, the first to be equipped with safety devices, was laid to defend the city. During the battle a mine destroyed the monitor USS TECUMSEH, the newest and most powerful of all the Federal ironclads. TECUMSEH. constructed at a cost of about one million dollars, was destroyed by a mine with a cost of less than one hundred dollars. Later on December 9, mines detonated from shore destroyed seven of 12 Federal vessels moving up to the Roanoke River to capture Fort Branc, North Carolina.

Maury was correct with his vision of mines as effective defensive weapons. During the War more Union ships were lost to mines than to any other weapon. Further, mines prior to the Civil War some-times floated toward enemy shipping and provided opportunity for an avoidance maneuver. Mines now successfully being placed beneath the surface added a new dimension to their lethality and the consequent deterrent impact on coastal or river intruders. Neither of the navies overlooked offensive use of the mine. Both sides investi-gated drifting mines and the spar torpedo from torpedo boats and ironclads.

Similar to the case of other weapons, mine countermeasures slowly evolved. T. M. Melia in Damn the Torpedoes: A Short History ofU. S. Na val Mine Countermeasures, 1777-1991 points out that earliest countermeasures included bow watches or personnel in small boats looking for mines. Contact mines, if located were sunk with a properly placed bullet hole. Later, other countermeasures developed.

With the Confederate Navy planting the mines, the Federal forces took the initiative to counter the mines. The 1997 book Shades of Blue and Gray points out that the Union Navy devised a defensive mechanism, the world’s first mine sweepers. To assist Union ships transiting inland waterways of the South, first use of such a device occurred on 30 April 1862. The first countermeasure was attached to the bow of a monitor modified for minesweeping. A primary sweeping device consisted of a huge rake 65 feet long. Affixed to it were large numbers of grappling hooks, pushed ahead of a lead vessel. A symposium held in 2000 at the Navy Postgraduate School also referred to the device; “One invention was the wood and bamboo ‘cow catcher’. It was designed to stand out from the Clad’s bow 20 to 30 feet and acted as false front. One was attached to the monitor USS SAUGUS and used during the James River Operation. They called this device a ‘torpedo catcher’ or ‘torpedo rake’. At the same time, the US Navy also experimented with fish nets extending from all sides of the ship to protect against contact mines.” During the Civil War, of forty-three Federal ships struck by Confederate mines, twenty-seven sunk. The Confederacy’s success with mines brought global attention to the mine as an effective weapon.

Post Civil War-1900

The first half of the 191h century brought improvements in mine performance and its utilization. Several European conflicts provided opportunities for implementation. This helped to establish the mine’ s credibility always as a deterrent even in cases where its performance was limited. Stealth quality of the mine when buried beneath the sea was recognized, an “invisible” weapon. This particular aspect of the mine brought contempt in some circles and a somewhat negative approach to its development and ultimate use. This opinion of mines persisted. Mines were judged as “unworthy and improper to the conduct of wars”.

Mines saw use in the Paraguayan War (1865-7-). Argentina, Brazil, and Uruguay War opposed Paraguay. Mines laid in the Paraguay River cost Brazil one monitor. Paraguay lost the war but interest in mine warfare was sustained in the Latin American navies.

European navies also began to regularly use mines detonated mechanically and electro-mechanically. For instance, during the Franco-Prussian War (1870)~ with Franco-Prussian War 1870, the Prussians publicized the fact that they were laying mines in an attempt to keep the superior French fleet away from its ports. Realizing that merely the fear of mines might keep the French Navy at bay, the Prussians even laid dummy weapons when production of real mines ran behind schedule.

Hertz horn-50 year detonator

Developed in 1868 by the North German Defense Committee, the Hertz horn electrical detonator continued in use through the first quarter of the 2o•h Century. As it projected outward from the outer surface of the mine, the word horn was an apt description of its appearance. To insure contact by the passing warship (vessel) several horns were mounted. The invention is attributed variously to a person by the name of Herz or Hertz. It was adapted by Russia to trigger their contact mines. The lead horns several inches long contained a glass tube of bichromate solution that would break when bent and produce a chemical reaction, electrically detonating the explosive. A charge of 35-53 pounds of dynamite and later TNT made the uncontrolled contact mine a feared weapon. By 1907, the wide and successful use of sea mines led to an international convention at The Hague concerning the laying of automatic submarine contact mines. The Hertz detonator, in addition to persisting as a dependable device, has also exhibited the characteris-tic of being operable even after years of submersion. Some modem mines in the 21 ‘1 century are equipped with horns similar to those of the I 81h century design.

Naval Torpedo Station (Newport, Rhode Island 1869

In 1869, Civil War Admiral David Porter(l813-1891), appointed by President Grant as assistant to the Secretary of the Navy, was instrumental in establishing under the Navy’s Bureau of Ordnance (BuOrd) a new experimental Naval Torpedo Station (NTS) at Newport, Rhode Island. Porter’s Civil War experience included mines and his plan for the new station involved hands-on experi-ments with torpedoes, mines, explosives, electrical devices to detonate them, and countermeasures to determine how the new technology should be used. He pushed for mines to be a high priority in the Navy and formed a Torpedo Corps within the Navy’s Bureau of Ordnance. Initially Naval defense mines were the responsibility ofNTS. The mine cases were an outside contract with all parts and fittings manufactured and assembled at the Station.”

The original site for NTS included former Anny buildings on Goat Island in Newport harbor and buildings used by the Naval Academy at Newport during the Civil War. Until the mid-1880s, primary attention at the Station addressed understanding and improving the spar torpedo (mine) and the towed mine. Both mining and countermining (MCM) were on the agenda of the original commanding officers at NTS.

Underwater use of electric lights to locate mines was examined, along with other ship self-protection measures. The underwater use of electric lights to spot mines was evaluated at NTS, and in 1884, the Navy ordered “torpedo searchlights” for installation on its new cruisers.

Awareness and growing interest by the Navy in Whitehead’s self-propelled torpedo, invented in 1866, placed new demands on NTS. After 1885, work on mines and MCM lessened and automobile torpedo efforts increased and became dominant. In the first years of the 1900s, all of the Navy’s explosive development work at NTS was transferred to Indian Head, Maryland. Later in 1915, the manufac-turing of naval defense mines moved from NTS to Philadelphia, Pennsylvania, and Norfolk, Virginia, leaving the torpedo and related technology at Newport. This may have been due to budgetary considerations as well as the assignment of defensive mine work to the Army beginning in the 1870s. The broad acceptance of the mobile torpedo and the continuing improvement of its performance and accommodating it on the various types of naval vessels placed additional space requirements on the facilities at the NTS.

Russia and Mine Warfare

European Countries observed the United States Confederacy’s defensive mining successes during the Civil War and in 1875, Russia established a mine warfare school in St. Petersburg for the Baltic and Black Sea fleets. In 1877, the Russian Naval Academy at Nikolaiev instituted new courses on strategy and mine warfare. Hertz horn contact mines and electrically controlled observations mines provided coastal defense in the somewhat shallow Baltic approach to St. Petersburg in the Gulf of Finland and along the Black Sea coast near Odessa.

During the Russian-Turkish War, ( 1877-78), a superior Turkish Navy opposed the Russian on the Black Sea. With mines and Whitehead’s torpedoes, Russia immobilized the Turkish opposition. This victory provided further proof of the efficacy of the mine as an important weapon in offensive warfare.

United States Army Mines

The United States Congress recognized sea mines as a method of harbor and coast defense when submarine mining was added to the activities of the Engineering Corps of the Army. In 1871, General Abbot conducted mine experiments at Fort Totten, Willets Point, New York at the west end of Long Island Sound. Later, an experi-mental floating controlled minefield was planted in the Potomac River near Fort Washington,just south of Washington, DC. The 147 electrically-detonated mines were held in place 10 to 20 feet below the surface by 1000-pound anchors.

During the Spanish-American war in 1898, live mines were activated at the Potomac River installation. At this time, an attempt was made to develop a minefield for the New York harbor but failed due to poor condition of the equipment and a complete lack of technical knowledge. The laying of mines in harbors did not alleviate the safety concerns of the United States port cities. This situation continued through World War I and the U.S. Anny was unable to plant any mines in the defense of the United States.

During the nine month war (April 24, to December 10, 1898) the Spanish directed by Admiral Pascual Cervera effectively used electrically activated mines, the fort’s guns, that overlooked the harbor at Santiago, Cuba, and log barriers. USN Captain William T. Sampson, acting Admiral in charge of the blockade of Cuba, was not able to enter the four-mile inlet leading into the port to attack the Spanish fleet.19 The war exposed how limited were the U. S. Navy’s mine warfare capabilities. Sea mines were still considered unconven-tional and not creatively used.

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