View source for Oakum

{{short description|Tarred fiber}}
[[Image:Drev och drevjärn samt träklubba 004.jpg|thumb|Oakum and tools for caulking]]
[[Image:Hennepvezel Cannabis sativa fibre.jpg|thumb|Hemp]]
[[File:Coldbath-fields-oakum-room-mayhew-p301.jpg|thumb|Prisoners picking oakum at [[Coldbath Fields Prison]] in London]]

'''Oakum''' is a preparation of [[tar]]red fibers used to seal gaps. Its traditional application was in [[shipbuilding]] for [[caulk]]ing or packing the joints of timbers in wooden vessels and the [[Deck (ship)|deck]] planking of iron and steel ships.<ref name=EB1911>{{EB1911 |inline=y |wstitle=Oakum |volume=19 |page=935}}</ref> Oakum was also used in plumbing for sealing joints in [[cast iron pipe]], and in log cabins for [[chinking]]. In shipbuilding it was forced into the seams using a hammer and a caulking iron, then sealed into place with hot [[Pitch (resin)|pitch]].<ref name="Kemp1979">{{cite book |last=Kemp |first=Peter |title=The Oxford Companion to Ships & the Sea |url=https://books.google.com/books?id=8VmnPwAACAAJ |year=1979 |publisher=Oxford University Press |isbn=978-0-586-08308-6 |page=807}}</ref>

It is also referenced frequently as a medical supply for medieval surgeons, often used alongside bandages for sealing wounds.<ref name="de Chauliac1353">{{cite book |last=de Chauliac |first=Guy |title=The Major Surgery of Guy de Chauliac |year=2007 |isbn=978-1425773168 }}</ref>

==History==
The word oakum derives from [[Middle English]] ''{{lang|enm|okome}}'', from [[Old English]] ''{{lang|ang|ācumba}}'', from ''{{lang|ang|ā-}}'' ([[ablative case|separative]] and [[perfective aspect|perfective]] prefix) + ''{{lang|ang|-cumba}}'' (akin to [[Old English]] ''{{lang|ang|camb}}'', "comb")—literally "off-combings".

Oakum was at one time recycled from old [[Tarring (rope)|tarry ropes]] and cordage, which were painstakingly unravelled and reduced to fibre, termed "picking". The task of picking and preparation was a common occupation in prisons and [[workhouse]]s,<ref name=EB1911/> where the young or the old and infirm were put to work picking oakum if they were unsuited for heavier labour. Sailors undergoing naval punishment were also frequently sentenced to pick oakum, with each man made to pick {{convert|1|lb|g}} of oakum a day. 

The work was tedious, slow and taxing on the worker's thumbs and fingers.<ref name="Kemp1979"/>  In 1862, girls under 16 at [[Tothill Fields Bridewell]] had to pick {{convert|1|lb|g}} a day, and boys under 16 had to pick {{convert|1+1/2|lb|g}}.<ref name=Mayhew>{{cite book |title=The Criminal Prisons of London, and Scenes of Prison Life |series=Volume 3 of The Great Metropolis |first1=Henry |last1=Mayhew |first2=John |last2=Binny |publisher=Griffin, Bohn, and Company |location=London |year=1862 |url=https://archive.org/details/criminalprisons00binngoog |page=[https://archive.org/details/criminalprisons00binngoog/page/n564 477] }}</ref> Over the age of 16, girls and boys had to pick {{convert|1+1/2|and|2|lb|g}} per day respectively.<ref name=Mayhew/> The oakum was sold for £4 10s ({{Inflation|UK|4.5|1864|fmt=eq|cursign=£}}) per [[imperial hundredweight|hundredweight]] ({{convert|112|lb|disp=comma|abbr=on}}).<ref name=Mayhew /> At [[Coldbath Fields Prison]], the men's counterpart to Tothill Fields, prisoners had to pick {{convert|2|lb|g|abbr=on}} per day unless sentenced to hard labour, in which case they had to pick between {{convert|3|and|6|lb|abbr=on}} of oakum per day.<ref>Mayhew & Binny (1862) p. 312.</ref>

In modern times, the fibrous material used in oakum comes from virgin [[hemp]] or [[jute]]. In plumbing and marine applications, the fibers are impregnated with tar or a tar-like substance, traditionally [[pine tar]] (also called "Stockholm tar"), an amber-coloured [[pitch (resin)|pitch]] made from pine sap. Tar-like petroleum by-products can also be used for modern oakum. "White oakum" is made from untarred material,<ref name=EB1911/> and was chiefly used as packing between brick and masonry in homes and building construction prior to [[World War II]], as its breathability allows moisture to continue to wick and transfer through the material.

==Plumbing==
Oakum can be used to seal [[cast iron pipe]] drains. After setting the pipes together, workers pack oakum into the joints, then pour molten [[lead]] into the joint to create a permanent "lead and oakum" seal. The oakum swells and seals the joint, the tar in the oakum prevents rot, and the lead keeps the joint physically tight. Oakum present in older cast iron bell/spigot joints may also contain [[asbestos]], requiring special methods for removal.

Today, modern methods, such as rubber seals (for example, [[gasket]]s or [[o-ring]]s), are more common.<ref>{{cite web |url=http://contractormag.com/columns/yates/cm_column_379/ |title=The Lost Art of Making Lead Joints |last1= Yates |first1= David |date= 1 February 2005 |publisher=Contractormag.com |access-date=6 July 2011}}</ref>

==Cultural references==
In [[Herman Melville]]'s novella ''[[Benito Cereno]]'', crew members of a slave ship spend their idle hours picking oakum.

[[Charles Dickens]]'s novel ''[[Oliver Twist]]'' mentions the extraction of oakum by orphaned children in the workhouse. The oakum extracted is for use on navy ships, and the instructor says that the children are serving the country.

''[[The Innocents Abroad]]'', a travel book by [[Mark Twain]], also mentions in chapter 37 a "Baker's Boy/Famine Breeder" who eats soap and oakum, but prefers oakum, which makes his breath foul and teeth stuck up with tar.

{{poemquote|text=We tore the tarry rope to shreds
  With blunt and bleeding nails;
We rubbed the doors, and scrubbed the floors,
  And cleaned the shining rails:
And, rank by rank, we soaped the plank,
  And clattered with the pails.
| sign =[[Oscar Wilde]]
| title=''[[The Ballad of Reading Gaol]]''
| source=1897}}

[[Jack London]], in his book ''[[The People of the Abyss]]'' (1903), mentions picking oakum in the workhouses of London.

[[Robert Jordan]], in ''[[Winter's Heart]]'' alludes to picking oakum as a punishment among the Sea Folk.

[[Joshua Slocum]] in ''[[Sailing Alone Around the World]]'', describes caulking his ship the ''Spray'', with oakum.

[[Guy de Chauliac]] in ''[[The Major Surgery of Guy de Chauliac]]'', frequently cites oakum as a medical supply in his treatments of wounds.

[[Bernard Cornwell]], in his [[Sharpe (novel series)|Sharpe]] novels, refers to Richard Sharpe's childhood in a workhouse, picking fibres from old rope.

==References==
{{reflist}}

{{Plumbing}}

[[Category:Hemp products]]
[[Category:Jute]]
[[Category:Shipbuilding]]
[[Category:Surgery]]