Posted on 08/28/2018 10:55:58 AM PDT by SunkenCiv
Thousands of shipwrecks litter the seafloor all over the world, preserved in sediments and cold water. But when one of these ships is brought up from the depths, the wood quickly starts deteriorating. Today, scientists report a new way to use "smart" nanocomposites to conserve a 16th-century British warship, the Mary Rose, and its artifacts. The new approach could help preserve other salvaged ships by eliminating harmful acids without damaging the wooden structures themselves.
The Mary Rose sank in 1545 off the south coast of England and remained under the seabed until she was salvaged in 1982, along with over 19,000 artifacts and pieces of timber. About 40 percent of the original structure survived. The ship and its artifacts give unique insights into Tudor seafaring and what it was like to live during that period. A state-of-the-art museum in Portsmouth, England, displays the ship's hull and artifacts.
While buried in the seabed, sulfur-reducing marine bacteria migrated into the wood of the Mary Rose and produced hydrogen sulfide. This gas reacted with iron ions from corroded fixtures like cannons to form iron sulfides. Although stable in low-oxygen environments, sulfur rapidly oxidizes in regular air in the presence of iron to form destructive acids. Corr's goal was to avoid acid production by removing the free iron ions.
Once raised from the seabed, the ship was sprayed with cold water, which stopped it from drying out and prevented further microbial activity. The conservation team then sprayed the hull with different types of polyethylene glycol (PEG), a common polymer with a wide range of applications, to replace the water in the cellular structure of the wood and strengthen its outer layer.
(Excerpt) Read more at eurekalert.org ...
Marine archaeology has advanced considerably over that last 50 years. My last visit to Mary Rose was early on in the restoration. Much has been done since those early days.
Kansas City has a 1850’s steamboat, the Arabia, that sank in the Missouri River and was left in a farm field when the course of the river changed. The preservation is remarkable, some of the foodstuffs were edible and the trade goods looked like they just came from the factory. The ship was well preserved, but only a portion of it was conserved. Well worth a visit and closer to Portsmouth for those on this side of the pond.
LOL! England was a magnet for people fleeing religious persecution throughout Europe, so a lot of Italians and other people from Italy, and French, and Germans, etc etc wound up there. By the late 16th c, Shakespeare was writing plays, and in a relatively short career (ending under James I/VI, who loved Shakespeare's work even before he was crowned, such that Shakespeare was one of the people appointed to hold up the royal canopy during the coronation. Oh, but don't forget, Shakespeare was illiterate and was barely able to stand up and hold the canopy at the same time) produced Othello (black protagonist), and collaborated on the unfinished "Sir Thomas More" which was about racial intolerance while superficially about something else (the manuscript is the longest sample of his handwriting in existence).
Also, Henry VIII can be credited as father of the British Navy -- he imported coal miners and metallurgists from some of the German states in order to replace naval and field guns with iron-based versions (the bronze cannon were expensive and unreliable, even dangerous to use), which tended to make vessel redesign a learn-by-doing affair until they were no longer topheavy.
Thanks!
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