Types of Fuzes

     A Fuze, or detonator, is anything which serves as a causative agent to make another agent burn or explode.  Blackpowder by itself cannot be exploded.  It needs some sort of outside source of heat or spark to make the reaction occur.  During the Civil War, several methods were experimented with and used to detonate blackpowder.  Some methods originally for other purposes were modified to use in torpedoes.

Friction Primer Fuze

     Common friction primers came in several sizes and compisitions.  The most common friction primer was the artillery friction primer.  This primer was a small brass tube filled with gunpowder.  On top of the main tube was another tube fitted perpendicular to the main tube.  In this second tube was a composition that was sensitive to friction.  A wire with rough serrations was fitted into the composition when the tube was manufactured.  When used in field, the roughened wire was pulled through the friction mixture and a spark was generated.  This spark ignited the mealed blackpowder in the main tube, which in turn communicated the spark to the main charge in the barrel of the artillery piece.  Artillery friction primers came in several sizes to fit the many calibers of guns.

     There was also a cannon primer constructed from a goose quill.  This cannon primer was used aboard ships, where gun crews were often sandwiched between decks with thier naval cannon.  When cannons are fired, the friction primer, if of brass, blows out of the primer hole and becomes a small missile which can maim of kill.  Naval primers, being of goose quill, burned up with the firing of the primer and, therefore, posed no threat to the crews.  Metallic friction primers were used aboard a ship in emergencies or when the quill primers would not make a weapon fire for some reason.  Although there is no record of a quill primer being used in a torpedo, it is possible that they could have been.

Percussion Cap Fuze

     Percussion caps are used to detonate the charge of a rifle, pistol, or shotgun.  Percussion caps are small brass caps containing a small amount of fulminate of mercury.  When the hammer of the gun crushes the cap, the fulminate of mercury is activated, causing a spark.  this spark is communicated through the nipple of the weapon to the main charge in the barrel.  Percussion caps require the use of a spring-loaded hammer, or heavy wieght, to fall on the cap and a hollow nipple to communicate the resultant spark to the main charge.

Electric Fuze

     As electricity was experimented with, it became obvious that when a charge of electricity if forced through a wire [called a bridge wire in current parlance] of a small diameter, because of the bridge wire's resistance to the flow of electrons, the bridge wire heats.  Certain metals, notably platinum (sometimes referred to as platina), became hot faster that other metals.  When the bridge wire becomes hot enough, it will detonate blackpowder.

     If electricity is forced through a wire a small gap is made in the wire, the electricity will attempt to bridge the gap, creating a spark.  A spark of sufficient intensity will detonate blackpowder.  If the gap is too small, an insufficient spark will occur.  However, if the gap is too large, the electricity will not attempt to cross the gap and no spark will occur.

     To provide current in the electric fuzes, a number of methods were imployed by operators.

• Galvanic Cells -The theory of galvinism involves a chemical reaction between common acids and common metals.  The reaction results in an electrical current being generated from the positive pole of the galvanic cell. 
• Wheatstone Magnetic Exploder- Several scientist, including Dr. Wheatsone, using Faraday's Law, learned that by moving magnets rapidly past other permanent magnets, a charge of electricity could be generated.  This device was adapted by the Confederates to torpedo usage.  With the Wheatstone Magnetic Exploder, the torpedo operator could wait until the enemy ship neared the torpedo, crank up enough current to detonate the torpedo an then open a switch to complete the connection.
• Beardslee's Magneto-Electric Machine- G.W. Beardslee of New York, invented a device that was very similar to Wheatstone's.  In Beardslee's generator, the disc ran in a horizontal plane past the necessary magnets and coils.  Most of his inventions were made for use in telegraphy.
• Wet Cell (Bunsen) Batteries in Jars- Acid in zinc and clay cups were also used for the purpose of generating electricity in torpedoes.

     The hardest part of using an electric means of detonating a torpedo was the lack of quality wire in the Confederacy, this included both insulated wire for running the leads from the source of current to the torpedo fuze and the platinum wire used as the bridge wire in the fuze.  Transportation and setup was also difficult in the use of the wet cell and galvanic batteries as they were complex and required space, ventilation, and wagons to transport. 

Acid Chemical Fuze

     Chemical creation of fire was known for hundreds of years before the Civil War.  By 1861, it was well known that sulphuric acid acting on a compound of potassium chlorate and common sugars creates fire.  The foundation for chemical fuzes in trpedoes followed that, or a very similar, formula.  The sulphuric acid fuze is sometimes referred to as the Dr. Jacobi fuze.

     Jacobi-type acid fuzes were used on some frame torpedoes in and near Charleston, SC.

     Jacobi type fuzes were also in use by the U.S. Navy forces in July 1864 on thier spar torpedoes. 

Hydrogen Gas Chemical Fuze

     A special chemical fuze was created near the end of the war.  It used hydrogen gas forced of a pice of spongy platinum to create heat sufficient enough to explode the main charge in the torpedo.

Match Fuze 

     Slow match and quick match had been used by the Ameican Military since the Revolution .  Match was nothing other than a cotton cord.  The cord is soaked in a solution of of potassium chlorate and allowed to dry.  When lit, the cord burns at a fixed rate.  The slow match (with a lower percentage of potassium chlorate) burned at a very slow rate. The quick match, containing a higher concentation burned at a much faster rate.

Raines Sensitive Fuze

     The ultimate specialized torpedo primer was the Raines Sensitive Fuze Primer.  General Gabriel Raines, head of the Confederacy's Torpedo Bureau. developed his fuze specifically for use in torpedoes.

     After some experimentation, Raines found that a compound of antimony sulfide, ground glass, and potassium chlorate provided a substance that was extremely sensitive to mechanical pressure.  When completed, the fuzes ignited into flame when a pressure of about 7 pounds was forced against them.

     This torpedo fuze required a bouching in the body of the torpedo threaded to accept the exterior threads of the fuze.  There were two variations of the fuze based on how the sensitive primer was adjusted within th fuze body.

• Screw thread adjustment- In this version the sensitive primer is held in place by a threaded cylinder.  The external threads f the cylinder engage another set of threads within the body of the fuze.  By carefully screwing the cylinder into the completed fuze the sensitive primer can be brought up against the crushable cap without any intervening gap.  A lock nut holds th threaded cylinder in place and keeps it from backing off.  One fuze of this type used three sensitive fuze primers as a redundant firing systems to to insure ignition.
• Pinned cyclinder adjustment- In this variation, the sensitive primer is held in place by a simple, non-threaded cylinder.  The cylinder is slid into the hollow body of the fuze.  When in the approiate position, a pin is inserted through measured holes pre-drilled in both the fuze body and the cylinder.  This holds the sensitive primer in the appropriate position under the crushable cap.  A variant of this fuze uses, in lieu of a through pin, a set screw throuh the fuze body to hold the cylinder in place.
• Plunger activated fuze-  In this variation, the head of the fuze is covered by a hard metal dome.  the dome is pierced at the top and a solid metal plunger is pladed through the hole.  This plunder lays lightly in the think copper coverin of the sensitive fuze primer  When the plunger is struck, the plunger crushed the thin copper covering and the sensitive fuze primer ignitin the torpedo.
• Savannah variant- The primary difference with this fuze is that portion of the fuze that screws into the torpedo has a tapered, large thread as opposed to the straight, medium thread of the Screw thread adjustment fuze.  This variant s so named because of its origin and use at Savannah, GA.  This fuze was screwed straight into a drilled hole in the woden body of a keg torpedo without a bouching.

Abel's Magnet Fuze

     This fuze operated on the spark gap principal.  A chemical mixture of antimony sulphide was placed in the cap to serve as the initiator.  A crimped container held mealed powder.  The advantage lay in the two holes, which were connected to the fuze.  Two power lines (negative and positive) were pushed into the holes and th fuze became instantly useable. 

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