CHAIN

Some think there may be a connection between this unit of measurement and the anchor chain, but this is false. The chain is a surveyor's measuring tool, equal to 66 feet (Gunther's chain). The actual chain used by surveyors (before the advent of modern optical measuring tools) was comprised of 100 metal rods, each 8-inches long, connected with rings. One chain is equal to four rods. Ten chains equals one furlong, and ten square chains equals an acre. These are all land measurements and have nothing to do with the sea. From Wikipedia

LOFTING

The original plans for a boat are drawn to scale by the marine architect. With pencil and paper, he is able to refine the lines so that they run smoothly from frame to frame. He can emphasize the elements of speed, stability and buoyancy that he is trying to achieve with his concept for a new design.

When the time comes for construction to begin, those line drawings are recreated at full size, often on the floor of the workshop. That process is called "lofting". Usually there is a degree of art involved in boatbuilding, since nothing is made square. The reference points are marked on each station using careful measurements, and then those points are connected using sweeping curves drawn with the help of flexible battens.

When the lofting is complete, the boatbuilder can begin cutting and shaping each piece, using the lofting drawings for his reference.

ELECTROLYSIS

Sea water is salty, the result of river waters carrying salts out of the rocks of the earth during endless millennia, and washing those chemicals down to the oceans. The salt makes ocean water more buoyant, so that a person or a ship actually floats higher in salt water than in fresh water. The salt content also makes sea water a fairly good electrolyte, meaning that the liquid can more easily conduct electricity. The underwater parts of boats and ships often expose different metals to that electrolyte creating a kind of battery. One metal, such as the bronze of the propeller may lose electrons through the water to the stainless steel drive shaft. Over time this will cause pitting of the propeller, weakness and eventually failure. That devastating process is called "electrolysis".

FLOTSAM AND JETSAM

Jetsam refers to any of a ship’s gear or cargo that is purposely thrown overboard in an emergency. The term is derived from the word "jettison", and refers to all items sacrificed to lighten the ship, whether those items sink or float. Flotsam describes floating debris from a shipwreck at sea.

BAGGYWRINKLES

Even without knowing the meaning of this term, you have to admit this one is really charming. To get the meaning, you have to picture the sails sometimes filled and drawing hard against the shrouds, or sometimes slapping against the standing rigging during a tack or when the wind shifts suddenly. That kind of friction will wear out the sails, and cause tears and holes. To protect the sails, seamen used to improvise chafing gear out of old rope, wrapping it around the shrouds so that the strands stick out, providing a soft cushion for the sails. That chafing gear is called baggywrinkles.

BUCCANEER

One of the SeaTalk contributors, John Hutchinson, suggested that we provide more information about this term. It comes from the French word "boucan" meaning smoked meat. Back in the 17th Century, freebooters used to stop at islands in the Caribbean and poach cattle, then preserve the meat by smoking it for their own use and for resale at the market. The French word for smoke is "boucane", and the smoked meat was called "boucan". The scoundrels who engaged in this trade in stolen meat were known as "boucaniers". When the term was Anglicised, it became "buccaneers". They were the forerunners of the pirates of the Caribbean.

AVAST

Here's an archaic term often used in pirate movies: "Avast, me hearties!" Probably the script writers had no idea what this meant; it just sounded nautical. In fact the term comes from the Dutch, and means "hold fast!" It's good to know the term, but don't use it, unless you don't mind sounding foolish.

ABOVE BOARD

Today, above board means without deceit or trickery, and the term comes right out of the seafaring traditions. The board refers to the topmost plank in the siding, and that important slab of wood shows up in numerous seafaring terms, such as on board, overboard, inboard, by the board and others. Back in the days of the buccaneers, when a pirate ship approached another vessel at sea, most of the crew would hide below so that there appeared to be no threat. On the other hand, when the crew could be seen "above board", that signified they were not being deceitful about their intentions.