Editing Lock and key (section)

===Modern locks===
[[File:Tibetan Lock and key - Dhankhar Gompa, Spiti. 2004.jpg|thumb|Tibetan Lock and key – [[Dhankhar]] Gompa, [[Spiti]]. India. 2004]]
[[File:Chinese lock.JPG|thumb|Chinese lock and key from [[Yunnan Province]], early 20th century|alt=]]
[[File:Key anatomy.jpg|thumb|Key anatomy]]
With the onset of the [[Industrial Revolution]] in the late 18th century and the concomitant development of precision engineering and component standardization, locks and keys were manufactured with increasing complexity and sophistication.<ref>{{Cite book |last1=Abreha |first1=Kaleb G. |url=https://books.google.com/books?id=_71VEAAAQBAJ&dq=With+the+onset+of+the+Industrial+Revolution+Locks+and+keys+were+manufactured+with+increasing+complexity+and+sophistication.&pg=PT77 |title=Industrialization in Sub-Saharan Africa: Seizing Opportunities in Global Value Chains |last2=Kassa |first2=Woubet |last3=Lartey |first3=Emmanuel K. K. |last4=Mengistae |first4=Taye A. |last5=Zeufack |first5=Albert G. |date=2021-12-18 |publisher=World Bank Publications |isbn=978-1-4648-1721-2 |language=en |access-date=2022-05-18 |archive-date=2023-11-10 |archive-url=https://web.archive.org/web/20231110054823/https://books.google.com/books?id=_71VEAAAQBAJ&dq=With+the+onset+of+the+Industrial+Revolution+Locks+and+keys+were+manufactured+with+increasing+complexity+and+sophistication.&pg=PT77#v=onepage&q=With%20the%20onset%20of%20the%20Industrial%20Revolution%20Locks%20and%20keys%20were%20manufactured%20with%20increasing%20complexity%20and%20sophistication.&f=false |url-status=live }}</ref>

The [[lever tumbler lock]], which uses a set of levers to prevent the bolt from moving in the lock, was invented by [[Robert Barron (locksmith)|Robert Barron]] in 1778.<ref name=EB1911>{{cite EB1911 |wstitle=Lock |volume=16 |pages=841–844 |first=Arthur Brunel |last=Chatwood}}</ref> His double acting lever lock required the lever to be lifted to a certain height by having a slot cut in the lever, so lifting the lever too far was as bad as not lifting the lever far enough. This type of lock is still used today.<ref>{{cite book|last=Pulford|first=Graham W.|title=High-Security Mechanical Locks : An Encyclopedic Reference|url=https://archive.org/details/highsecuritymech00pulf_549|url-access=limited|year=2007|publisher=Elsevier|isbn=978-0-7506-8437-8|page=[https://archive.org/details/highsecuritymech00pulf_549/page/n331 317]}}</ref>

[[Image:Chubb lock.jpg|thumb|Diagram of a [[Chubb detector lock]]]]
The lever tumbler lock was greatly improved by [[Jeremiah Chubb]] in 1818.<ref name=EB1911/> A burglary in [[HMNB Portsmouth|Portsmouth Dockyard]] prompted the [[Government of the United Kingdom|British Government]] to announce a competition to produce a lock that could be opened only with its own key.<ref name=":1" /> Chubb developed the [[Chubb detector lock]], which incorporated an [[Combination lock#Internal mechanisms|integral security feature]] that could frustrate unauthorized access attempts and would indicate to the lock's owner if it had been interfered with. Chubb was awarded £100 after a trained [[Lock picking|lock-picker]] failed to break the lock after 3 months.<ref>{{cite web|url=http://www.wolverhamptonhistory.org.uk/work/industry/lock_making2|title=Lock Making: Chubb & Son's Lock & Safe Co Ltd|publisher=Wolverhampton City Council|year=2005|access-date=16 November 2006|archive-date=10 January 2016|archive-url=https://web.archive.org/web/20160110131835/http://www.wolverhamptonhistory.org.uk/work/industry/lock_making2|url-status=dead}}</ref>

In 1820, Jeremiah joined his brother [[Charles Chubb (businessman)|Charles]] in starting their own lock company, [[Chubb Locks|Chubb]]. Chubb made various improvements to his lock: his 1824 improved design did not require a special regulator key to reset the lock; by 1847 his keys used six levers rather than four; and he later introduced a disc that allowed the key to pass but narrowed the field of view, hiding the levers from anybody attempting to pick the lock.<ref>{{cite book|author1=Roper, C.A. |author2=Phillips, Bill |name-list-style=amp |year=2001|title=The Complete Book of Locks and Locksmithing|publisher=McGraw-Hill Publishing|isbn=0-07-137494-9}}</ref> The Chubb brothers also received a patent for the first burglar-resisting [[safe]] and began production in 1835.

The designs of Barron and Chubb were based on the use of movable levers, but [[Joseph Bramah]], a prolific inventor, developed an alternative method in 1784. His lock used a cylindrical key with precise notches along the surface; these moved the metal slides that impeded the turning of the bolt into an exact alignment, allowing the lock to open. The lock was at the limits of the precision manufacturing capabilities of the time and was said by its inventor to be unpickable. In the same year Bramah started the Bramah Locks company at 124 Piccadilly, and displayed the "Challenge Lock" in the window of his shop from 1790, challenging "...the artist who can make an instrument that will pick or open this lock" for the reward of £200. The challenge stood for over 67 years until, at the [[Great Exhibition]] of 1851, the American locksmith [[Alfred Charles Hobbs]] was able to open the lock and, following some argument about the circumstances under which he had opened it, was awarded the prize. Hobbs' attempt required some 51 hours, spread over 16 days.

The earliest patent for a double-acting [[pin tumbler lock]] was granted to American physician Abraham O. Stansbury in England in 1805,<ref>{{cite book|title=The Complete Book of Home, Site, and Office Security: Selecting, Installing, and Troubleshooting Systems and Devices|year=2006|publisher=McGraw-Hill Professional|url=https://books.google.com/books?id=05ITGwH8rV8C&q=Abraham+O.+Stansbury+and+pin+tumbler+lock&pg=PA11|page=11|isbn=9780071467445|url-status=live|archive-url=https://web.archive.org/web/20161121072851/https://books.google.com/books?id=05ITGwH8rV8C&pg=PA11&dq=Abraham+O.+Stansbury+and+pin+tumbler+lock&hl=en&sa=X&ei=shDiT-2pMofO9QTf66CHCA&ved=0CDoQ6AEwAQ#v=onepage&q=Abraham%20O.%20Stansbury%20and%20pin%20tumbler%20lock&f=false|archive-date=2016-11-21}}</ref> but the modern version, still in use today, was invented by American [[Linus Yale Sr.]] in 1848.<ref>{{cite book|title=The Geek Atlas: 128 Places Where Science and Technology Come Alive|year=2009|publisher=O'Reilly Media, Inc.|url=https://books.google.com/books?id=HhEC0q-O1ewC&q=Linus+Yale%2C+Sr.+modern+pin+tumbler+lock&pg=PA445|page=445|isbn=9780596555627|url-status=live|archive-url=https://web.archive.org/web/20160501062428/https://books.google.com/books?id=HhEC0q-O1ewC&pg=PA445&lpg=PA445&dq=Linus+Yale,+Sr.+modern+pin+tumbler+lock&source=bl&ots=MhDEksIeaw&sig=HqrCbHyFvLDC2BN5Mzt4SiFby_w&hl=en&sa=X&ei=r4PiT-vyCIn-8ATL57iGCA&ved=0CGIQ6AEwATgK#v=onepage&q=Linus%20Yale%2C%20Sr.%20modern%20pin%20tumbler%20lock&f=false|archive-date=2016-05-01}}</ref> This lock design used [[pin]]s of varying lengths to prevent the lock from opening without the correct key. In 1861, [[Linus Yale Jr.]] was inspired by the original 1840s pin-tumbler lock designed by his father, thus inventing and patenting a smaller flat key with serrated edges as well as pins of varying lengths within the lock itself, the same design of the pin-tumbler lock which still remains in use today.<ref>{{cite web|title=Inventor of the Week Archive|publisher=Massachusetts Institute of Technology|url=http://web.mit.edu/invent/iow/yale.html|url-status=live|archive-url=https://web.archive.org/web/20130529222941/http://web.mit.edu/invent/iow/yale.html|archive-date=2013-05-29}}</ref> The modern Yale lock is essentially a more developed version of the Egyptian lock.

Despite some improvement in key design since, the majority of locks today are still variants of the designs invented by Bramah, Chubb and Yale.