In the 1870s robbers stopped trying to beat bank locks and went after the people who knew the combination instead. The answer was a clock. Here’s how the time lock worked, who made it, what old ones are worth and how one can date a safe.
This article is about the clockwork time locks fitted to bank vaults and safes. The “time-locking safes” and timer boxes sold today for phones or snacks are a different thing.
1831
first clockwork time lock patented, in Scotland
1874
first Sargent & Greenleaf time lock fitted to a bank
$400
price of a two-movement time lock in 1874
16,000+
Yale Triple L time locks made, its best-selling model
Key takeaways
- A time lock is clockwork inside a safe or vault door that keeps it locked until a set hour, even for someone who knows the combination.
- It was the banks’ answer to “masked robberies”, in which gangs seized a cashier at home and forced him to open the safe at night.
- The idea dates from 1831, but James Sargent’s lock of 1874 was the first commercial success. Yale, Hall’s, Holmes, Mosler and Diebold followed.
- Locks carried two, three or four clock movements so that one failed clock couldn’t lock the bank out. A 72-hour run was standard by 1886.
- Maker names, dial wording, case finishes and patent dates make a time lock one of the easiest parts of an old safe to date.
In This Article
Time locks at a glance
| What it is | A clock-controlled lock that holds a safe or vault door shut until a preset time |
| Why | To stop robbers forcing staff to open the vault outside business hours |
| Earliest patent | William Rutherford of Jedburgh, Scotland, 1831 |
| First commercial success | Sargent & Greenleaf, Rochester, New York, 1874 |
| Main American makers | Sargent & Greenleaf; Yale (later Yale & Towne); Hall’s and the Consolidated Time Lock Co.; Mosler; Diebold |
| Movements | Usually two, three (“triple movement”) or four, any one of which can release the lock |
| Running time | 46 hours on the first Sargent locks; 72 hours standard by 1886; 96 and 120 hours as options by the late 1920s |
| In Britain | Chubb fitted American-made time locks about 1900 and sold its own from the 1960s, including the 7L60 |
| Still made? | Yes. Mechanical time locks are still fitted to large safes and vaults |
The problem: bank robbery by kidnapping
By the 1870s a good American bank safe was hard to break into before morning. So the robbers stopped attacking the safe and went for the person who could open it. In the language of the day this was the “masked robbery”: a gang entered the cashier’s or the bank president’s home at night, held the family and marched him to the bank to dial the combination. If he was lucky he was tied up and found in the morning. Some weren’t lucky.12
The cases read like a list of small-town banks. On 7 November 1873 Jimmy Hope and four other burglars, who had rented the house next door to the First National Bank of Wilmington, Delaware, captured the bank’s cashier and his whole family. The servant escaped and raised the alarm, and the gang were sentenced to forty lashes and ten years each.3 In January 1876 five masked men held John Whittelsey, cashier of the Northampton National Bank in Massachusetts, at his home until about four in the morning, when he gave up the keys and the true combination; the loss was put at a million and a quarter dollars.4
A safe that nobody could open until morning made the whole method pointless, and the first time locks were tested within months of going on sale. In 1875 gangs seized bank officers in Great Barrington, Massachusetts, and Barre, Vermont, and both raids failed because a time lock had just been fitted.56 Those two raids are told in full in our history of bank vault doors and the time locks that beat the kidnappers.
By 1876 even robbers had heard of them. When the James-Younger gang held up the First National Bank of Northfield, Minnesota, in daylight on 7 September 1876, the acting cashier, Joseph Lee Heywood, told them the safe was on a time lock and couldn’t be opened. He was shot dead.7 One researcher’s reconstruction of the raid says the bank’s new time lock hadn’t actually been set that day; either way, the bluff kept the gang out of the safe.8
Who invented the time lock?
Not an American, as it happens. In 1831 William Rutherford, a bank agent at Jedburgh in the Scottish Borders, patented a lock in which clockwork stopped the bolt being withdrawn, even with the proper key, until a set time.9 The idea then crossed the Atlantic in fits and starts. Francis Pye showed a time lock at the 1851 fair of the American Institute in New York, apparently a single exhibition piece that was never patented or fitted to a safe.1
The first that guarded real money came from Massachusetts. Amos Holbrook of Milford and Henry D. Fish of Hardwick patented a “chronometric lock” on 28 April 1857, US patent 17,150.10 Holbrook’s lock had two independent 72-hour movements acting on the bolt work, which is the whole modern principle in one go. It worked at the Milford Bank for eight years without trouble, but fewer than a dozen were made.1
Others tried in the early 1870s. Stephen W. Hollen of Cincinnati patented a time lock in December 1871 (US 121,782), and John Burge patented his “Gothic” time lock, named for its church-window case, in 1872.111 None of them sold in numbers. That took a salesman from Rochester.
James Sargent and Sargent & Greenleaf
James Sargent of Sargent & Greenleaf in Rochester, New York, already made bank combination locks when he applied for a time lock patent in June 1873. The Patent Office wasn’t impressed at first. The examiner rejected his main claim by pointing to Rutherford’s patent of 1831 and Holbrook’s lock, and the application went back and forth until January 1877, when it finally became US patent 186,369.1213 Sargent didn’t wait for it. The first of his time locks went into the First National Bank of Morrison, Illinois, in May 1874.14
That first year S&G offered two models. The Model 1 combined a time lock and a combination lock and was made in tiny numbers; the Model 2 was a separate two-movement time lock that blocked, or “dogged”, the safe’s bolt work, and it sold. It cost about $400 in 1874, and a time lock could cost as much as the safe it was fitted to.15 Sargent kept patenting improvements, such as a time lock of 20 July 1875 (US 165,878).16
The early locks had teething troubles, and one of them is a lovely detail for collectors. The very first Model 2 dials ran to 48 hours, but the springs turned out not to have enough power to run that long. S&G sent a circular to the banks that had already installed one, telling them to wind to 46 hours only, and swapped the dials for 46-hour ones at the next annual service. Only two locks with the original 48-hour dials are known.15
The rest is a steady line of models. The Model 3 of 1877 brought the low “drop bolt” that S&G used for decades, the smaller Model 4 followed in July 1878, and the three-movement Triple A, B and C arrived around 1888–1889. Unlike almost every rival, S&G made its own clock movements in Rochester. The company is the only maker from the 1870s still in the business: its time locks have been built in Lausanne, Switzerland, since 1978, and in 2005 it became part of Stanley.15
Yale, Hall’s, Holmes and the patent wars
Yale answered in 1875. Its first time lock, the Model 1 “double pin dial”, was built on a patent granted to Emory Stockwell, a long-serving Yale engineer, on 21 September 1875 (US 168,062).1718 It sold for about $400, or $450 with the optional “Sunday attachment” of 1878, which stopped the lock releasing on a Sunday.19 The movements came from E. Howard & Co. of Boston, which by 1885 charged Yale around $50 for a lock that Yale sold for $450. On top of that, banks paid about $10 a year for inspection and $5 more for cover against a lockout.1
Margins like that drew a crowd. Between 1874 and 1885 a string of small firms entered the trade, and about a dozen of them made fewer than 50 locks each.20 The Holmes Electric Time Lock Co. of New York built locks under Charles E. Chinnock’s patent, filed in 1876 and granted on 1 April 1879 (US 213,809), and ordered 105 sets of movements from E. Howard that July.2122 In St Louis, Beard & Brother sold time locks based on patents by their employee Phineas F. King, the first granted on 12 February 1878 (US 200,312).2324 In Cincinnati, Joseph L. Hall entered the business in 1875 and set up the Consolidated Time Lock Co. in 1880; his story, and his court fights with Sargent and Yale, are told in our history of Hall’s Safe & Lock Co.
The two big firms didn’t compete for long. On 16 October 1877 Sargent & Greenleaf and Yale signed a “Contract Respecting Time Locks” to share the market, thirteen years before the Sherman Antitrust Act made such deals illegal, and spent the next decade suing newcomers.18 Their joint catalogue of 1883 shows the two firms’ locks side by side at identical prices. The printer even put the Yale No. 1 in upside down, apparently assuming its dials sat at the top like Sargent’s, and the catalogue needed a correction slip.15
Mosler, Diebold and the twentieth century
The big safe makers came in later. Mosler Safe & Lock Co. bought Beard & Brother’s time lock patent rights in 1887 and started with a two-movement lock based on them.24 The separate Mosler Safe Co. brought out its own time locks in 1915–1916, using pocket watch movements from the Illinois Watch Co., then Waltham movements from 1933 and Swiss Recta movements from the 1950s.25 Diebold didn’t make a time lock until 1894, when it launched a model with three 72-hour movements; it bought the Chicago Time Lock Co. around 1908.26 Buffalo’s Cary Safe Company made its own under George Goehler’s 1891 patent, covered in our history of Cary safes.
Timeline
- 1831 William Rutherford of Jedburgh patents a clockwork bank lock.
- 1857 Holbrook and Fish patent their two-movement chronometric lock.
- 1874 Sargent & Greenleaf’s first time lock goes into a bank at Morrison, Illinois.
- 1875 Yale and Hall’s enter the time lock business.
- 1877 Sargent & Greenleaf and Yale agree to share the market.
- 1886 72 hours becomes the standard running time.
- 1887 Mosler Safe & Lock Co. buys Beard & Brother’s time lock rights.
- 1894 Diebold makes its first time lock.
- 1929 The Depression all but stops time lock sales until after the Second World War.
The 1929 date comes from the collectors’ histories: time lock production at all the main makers virtually stopped with the Depression and didn’t recover until a few years after 1945. Many old locks were lost in the wartime metal drives, broken up for the bronze in their cases. Yale stopped making time locks in the United States by the 1950s and sold its bank lock division to Diebold in 2000.1518
How a time lock works
Open the glass door of an old time lock and you’ll see what is really a small, very solid clock, or two, three or four of them side by side, each with a dial marked in hours. Before closing the vault for the night, staff wound the movements and set them for the number of hours until the next opening. While any movement was still running, the lock was “on guard”: a blocking piece held the door’s bolt work so it couldn’t be withdrawn, or, on some designs, held the combination lock itself. Dialling the right combination made no difference.1
When the first movement ran down, the lock went “off guard”. On most doors that didn’t open anything by itself; it simply meant the combination would now work and staff could throw the bolts back as usual.20 Some vault doors had spring-powered automatic bolt motors instead of a handle, which could only work with a time lock to trigger them.15
Redundancy
Two to four movements
Any one movement could release the lock, so a single stopped clock couldn’t shut the bank out of its own vault. Two was the norm in the 1870s; three and four came later.15
Hours
72 to 120 hours
Sargent’s first dials gave 46 hours. A 66-hour version followed in 1878, 72 hours was standard by 1886, and 96 and 120 hours were options by the late 1920s.15
“Triple movement” simply means three clocks. Yale’s Triple L, introduced in 1892, ran to more than 16,000 units, and a late-1920s Yale brochure claimed 30,000 Yale time locks in use.18 By 1951 Mosler’s standard seven-inch bank vault door could be ordered with a triple-movement 120-hour time lock.27 Four-movement locks were made for the largest vaults.
The extra hours cost real money. Sargent & Greenleaf’s price list of 22 April 1929 charged $311.10 for a Triple B with 72-hour movements, $355.54 with 96-hour movements and $477.77 with 120-hour ones, which is why long-running locks are scarcer today.15 And the extra movements weren’t all about safety. A collector who restores them points out that a small two-movement lock would do the same job as a massive four-movement one, but a dinky lock looked wrong on a massive vault door, and a big one earned the maker more.1
That’s as far as this page goes on mechanism. We don’t publish setting procedures, emergency releases or ways round a time lock; the general history of safe locks is in our guide to safe lock mechanisms from lever locks to time locks.
Time locks in Britain
Britain had the first patent and then, for a long time, very little else. A leading American collector writes that the United States was virtually the only country making time locks until well after the Second World War.1 We couldn’t find a British maker building its own time locks in quantity before the 1960s, though a 19th-century one may yet turn up.
Chubb, the biggest British name, bought in. The Chubb Archive has a time lock of about 1900 marked “CHUBB” that was actually made by Sargent & Greenleaf under an agreement allowing a Chubb nameplate. It was fitted to a Chubb strongroom door made for display at a Paris exhibition, according to the archive in 1901, and the door then went into a Chubb vault at the London head office of one of the major British banks.28
Chubb began selling time locks under its own name in the 1960s. One two-movement Chubb model of the late 1960s used eleven-jewel movements by Smiths Industries.29 The 7L60 was a Chubb mechanical time lock fitted to its Bankers safes. In the 1970s Chubb’s Midlands manager took back a batch of third-strength Bankers safes from a Coal Board client, each with a 7L60, and replaced the time locks with a newer model. Because the 7L60 was popular in West Africa, the old locks were reconditioned by a watchmaker and sold to Chubb’s export department for £250 each.30 The Science Museum Group holds a Chubb electric time lock of 1970, made in Wolverhampton.31 More on the firm is in our history of Chubb safes.
When a time lock fails: lockouts
A time lock has one job it must never get wrong: it has to let the bank back in. A vault that stays shut on Monday morning means no cash for the counter and a door that may have to be forced, which is why one collector notes that a lockout is “the death knell for any time lock design”.29 Redundant movements, annual inspections and the lockout cover sold with them all existed to stop that happening.1
It mostly worked. The same collector writes that he knows of no documented lockout caused by a properly maintained mechanical time lock with two or more movements. The failures came with new technology: an electromechanical Chubb time lock of about 1970 caused a few lockouts and was recalled, and electronic time locks of the 1970s from Sargent & Greenleaf and Chubb suffered battery and component failures.129 If every movement did stop, the collectors’ sources are blunt: the door would have to be forced.20
If you own one
Never wind or set an old time lock with the door closed, and don’t close a door fitted with one until a qualified safe engineer has serviced the locks. If a door with a time lock is already shut and won’t open, don’t force it: a safe engineer is the only sensible call. Our guide to being locked out of an old safe explains your options and the costs.
Collecting antique time locks
Time locks are collected for the same reason clocks are: you can watch them work. They also survive in fairly small numbers. During the Second World War many were scrapped for the bronze in their cases and plates, and the ones that survive often owe it to safe technicians who took them out before a safe went for scrap. For the early makers only a few per cent of production is thought to survive.18
What collectors look for, according to the collectors’ own guides:151820
- Maker and model. Early Sargent & Greenleaf and Yale models, and anything from the short-lived makers of 1876–1882, are the prizes.
- Decoration. Ivy-leaf engraving on the earliest S&G movements, gold “jewelled” cases and original red-painted interiors.
- Matching numbers. Case and movement numbers that are close or consecutive suggest original movements; a jumble means swaps during service.
- Long running times, such as 120 hours, which few banks paid for.
- Visibility and condition. Full-glass doors show off the mechanism, and running movements matter.
Prices are modest next to the safes they came from. These are real auction results, not dealer asking prices:
| Time lock | Sale | Result |
|---|---|---|
| Yale Lock Mfg. Co. Model 1 double pin dial with Sunday dial, about 1880 | Schmitt Horan, October 2011 | $1,100 (estimate $1,000–1,200)19 |
| Yale Lock Mfg. Co. No. 3 double pin dial, E. Howard movement | Fontaine’s, November 2017 | $1,100 (estimate $2,000–3,000)32 |
| Yale & Towne two-movement, 72-hour dials | Fontaine’s, November 2017 | $400 (estimate $600–800)33 |
| Rare models (for example S&G for Cary, Holbrook) | A collector’s “wanted” list | “$1000 to over $5,000” offered, not a sale34 |
Treat those as an informal guide, not a valuation. Three sales from two American auction houses are a thin sample, and a working, original lock on its original safe is usually worth more as part of the safe; our guide to whether old safes are worth anything covers that side.
The collecting world is small and mostly American. Mark Frank’s online collection of about 300 time locks, organised by maker and number of movements, is the best free reference, and the standard book is John and David Erroll’s American Genius: Nineteenth-Century Bank Locks and Time Locks (2006).20 In New York, the John M. Mossman collection at the General Society of Mechanics and Tradesmen displays the bank locks and time locks donated by John M. Mossman, catalogued in 1928 as The Lure of the Lock.3520
How a time lock dates a safe
A time lock dates itself better than almost any other part of an old safe. Makers changed their names, dial wording, case finishes and running times at known dates, and many printed patent dates on the lock. Here are the clues the collectors use:
| What you see | What it suggests |
|---|---|
| Any time lock at all | Almost always 1874 or later14 |
| “E. Stockwell’s Patent, September 21st, 1875” (Yale) | Yale’s first patent, US 168,062; 1875 or later1719 |
| “Yale Lock Mfg. Co.” or “Yale & Towne Mfg. Co.” | The firm was renamed Yale & Towne in 1883, so Yale & Towne means 1883 or later36 |
| S&G dials with no maker’s name | Before 189615 |
| “Sargent & Greenleaf Company” on the dials | 1896 to 191815 |
| “Sargent & Greenleaf, Inc.” | 1918 or later15 |
| S&G plaque with dates from July 20, 1875 to Nov. 13, 1877 | 1877 or later15 |
| Gold “jewelled” S&G case; satin nickel case | Jewelled cases to about 1924; satin nickel standard from 192415 |
| Yale case: diamond-milled nickel; bronze “wave”; satin nickel | To about 1908; 1908 to about 1925; about 1925 to 192918 |
| Yale lock with winding holes in a metal lower door panel | After about 1905 (earlier doors were all glass)18 |
| Movements signed E. Howard (Diebold, Yale) | Usually before about 1902, when makers switched to Seth Thomas26 |
| Diebold time lock | 1894 or later26 |
| Mosler Safe Co. time lock | 1915–1916 or later (Mosler Safe & Lock Co. from 1887)2524 |
| Dials over 72 hours | 96 and 120 hours were 1920s options; 72 was standard from 188615 |
| “Made in Switzerland” on the dials | Post-war: Mosler used Swiss movements from the 1950s, S&G built in Lausanne from 19782515 |
| Chubb name on a time lock | Either an S&G-made lock of about 1900, or Chubb’s own from the 1960s on2829 |
Hall’s and Consolidated time locks have their own dating clues and serial ranges, set out in our history of Hall’s safes. One warning applies to all of them: a time lock dates the lock, not necessarily the safe. Locks were added to older safes, swapped between doors and fitted with new movements during decades of servicing. Look closely at the photo at the top of this page: two of the three Swiss-made Yale & Towne dials give different addresses, one Rye, New York, and one White Plains, so its movements didn’t all arrive together. A Yale & Towne lock sold in 2017 had one E. Howard movement and one attributed to Seth Thomas.33
Got a time lock on your safe? Write down every name, number and date on its dials, case and glass before anyone cleans it, and send us photos of the safe, its plate and the time lock. We’ll help you work out who made it and roughly when.
Time lock myths and facts
When the time runs out, the time lock opens the vault.
On most doors it only goes “off guard”. Staff still dial the combination and throw the bolts.
More movements make a vault harder to burgle.
Extra movements guard against a lockout, not a burglar. Any one of them can release the lock.
James Sargent invented the time lock.
The examiner who handled his 1873 application cited Rutherford’s 1831 patent and Holbrook’s lock. Sargent’s was the first to sell widely.
A “time lock safe” for sale today is the same thing.
Modern time-locking boxes are consumer timers. A bank time lock is a set of clock movements inside a safe or vault door.
Frequently asked questions
What is a time lock on a safe?
A set of clock movements inside the door that keeps the safe locked until a preset hour. Until it runs down, even the right combination won’t open the door.
Why do bank vaults have time locks?
So that nobody can be forced to open the vault outside business hours. They were adopted in the 1870s after gangs began kidnapping cashiers at night.
How long can a bank time lock be set for?
Up to the length of its dials. The first Sargent locks ran 46 hours, 72 hours became standard by 1886, and 96 and 120-hour versions were sold from the 1920s.
Can a time lock be opened early?
Not by design: that’s the point of it. If a time lock has failed or an old safe with one is shut, call a qualified safe engineer.
Who made the first time lock?
William Rutherford of Jedburgh patented one in 1831 and Holbrook and Fish another in 1857. James Sargent’s, first fitted in 1874, was the first commercial success.
How much is an antique time lock worth?
Recent auction results for Yale locks run from about $400 to $1,100, and rare early models can fetch more. Maker, model, originality and running condition decide it.
Are time locks still used?
Yes. Sargent & Greenleaf and Diebold still supply them, and mechanical time locks remain the usual choice for large safes and vaults.
Sources:
- Mark Frank, “A brief history of the time lock industry”, my-time-machines.net (bank vault time lock collection). ↩︎
- Mark Frank, “Short-lived time lock companies, 1876 through 1882”, my-time-machines.net. ↩︎
- Thomas Byrnes, Professional Criminals of America (New York: Cassell, 1886), p. 83 (James Hope) and the record of Frank McCoy, Cornell University Library copy via Internet Archive. ↩︎
- Cleveland Moffett, True Detective Stories from the Archives of the Pinkertons (New York, 1897), “The Northampton Bank Robbery”, via Project Gutenberg. ↩︎
- Bernard A. Drew, “The perilous lives of Great Barrington’s 49th Regiment volunteers, part II: Frederick Deland and the bungling bank robbers”, The Berkshire Edge, 26 May 2020. ↩︎
- The Vermont Historical Gazetteer, Barre chapter, “National Bank of Barre”, as transcribed by Vermont Genealogy. ↩︎
- Northfield History Center, “1876 Bank Raid”, Northfield, Minnesota. ↩︎
- James Allder, “A revised timeline of the 1876 Northfield robbery” (27 May 2013), a researcher’s reconstruction from contemporary reports. ↩︎
- Charles Tomlinson (ed.), Rudimentary Treatise on the Construction of Locks, from the papers of A. C. Hobbs (1853), chapter on Rutherford’s time lock, via Project Gutenberg. ↩︎
- Amos Holbrook and Henry D. Fish, US Patent 17,150, “Improvement in chronometric locks”, 28 April 1857. ↩︎
- Stephen W. Hollen, US Patent 121,782, “Improvement in time-locks”, 12 December 1871. ↩︎
- Sargent v. Hall Safe & Lock Co., 114 U.S. 63 (US Supreme Court, 30 March 1885), which sets out the prosecution history of Sargent’s application from June 1873, Legal Information Institute. ↩︎
- James Sargent, US Patent 186,369, “Improvement in time attachments for locks”, 16 January 1877. ↩︎
- Obituaries of James Sargent, Democrat and Chronicle and Union and Advertiser, Rochester, January 1910, transcription (PDF). ↩︎
- Mark Frank, “Sargent & Greenleaf, Rochester, New York, 1874 through today: introduction”, my-time-machines.net, drawing on John and David Erroll, American Genius (2006). ↩︎
- James Sargent, US Patent 165,878, “Improvement in time-locks”, 20 July 1875. ↩︎
- Emory Stockwell, US Patent 168,062, “Improvement in time-locks”, 21 September 1875. ↩︎
- Mark Frank, “Yale & Towne, 1875 through 2000: a brief history of the company and its time lock product line”, my-time-machines.net, drawing on John and David Erroll, American Genius (2006). ↩︎
- Schmitt Horan & Co., auction 1011 (October 2011), lot 211, Yale Lock Mfg. Co. double pin dial time lock, Model 1, with Sunday dial: estimate $1,000–1,200, sold $1,100. ↩︎
- Mark Frank, “Bank vault time lock collection”, my-time-machines.net, crediting John and David Erroll, American Genius: Nineteenth-Century Bank Locks and Time Locks (2006), and articles by David Christianson and James W. Gibbs. ↩︎
- Charles E. Chinnock, US Patent 213,809, “Improvement in time-locks”, 1 April 1879 (application filed 10 May 1876). ↩︎
- Mark Frank, “Holmes Electric Time Lock Company, New York, Models 1, 2 and 3”, my-time-machines.net. ↩︎
- Phineas F. King, assignor to G. N. and E. J. Beard, US Patent 200,312, “Improvement in time-locks for safes”, 12 February 1878. ↩︎
- Mark Frank, “Beard & Brother, St. Louis: introduction” and “Mosler Safe and Lock Co., Hamilton, Ohio, Model 1”, my-time-machines.net. ↩︎
- Mark Frank, “Mosler Safe Company, Hamilton, Ohio, 3 movements, Type 1” and “Bankers Dustproof Time Lock Co., Cincinnati”, my-time-machines.net. ↩︎
- Mark Frank, “Diebold Safe & Lock Co., Canton, Ohio, 1894 through today: introduction” and “Diebold 4 movements, Type 3”, my-time-machines.net. ↩︎
- The Mosler Safe Company, Bank Vault Door by Mosler, specification sheet for the No. RLD-7 seven-inch door, form B-2292 (December 1951, second printing), Tulane University Southeastern Architectural Archive, Building Technology Heritage Library via Internet Archive. ↩︎
- The Chubb Archive, “Lock stories” (Chubb-marked Sargent & Greenleaf time lock of about 1900). ↩︎
- Mark Frank, “Chubb, Wolverhampton, England”, my-time-machines.net (Chubb time locks of the 1960s to 1980s). ↩︎
- D. R. E. Ibbs, “Back to the Midlands” (his years as Chubb’s Midlands manager from April 1971), in Export is Fun, The Chubb Archive, chubbarchive.co.uk/page21. ↩︎
- Science Museum Group, “Electric time-lock by Chubb’s”, Wolverhampton, 1970, object 1970-348. ↩︎
- Fontaine’s Auction Gallery, lot 113, “Yale double pin dial bank vault time lock”, 11 November 2017: estimate $2,000–3,000, sold $1,100. ↩︎
- Fontaine’s Auction Gallery, Pittsfield, Massachusetts, lot 211, “Yale & Towne bank vault time lock”, 11 November 2017: estimate $600–800, sold $400. ↩︎
- Mark Frank, “Time locks wanted”, my-time-machines.net (a collector’s list of rare models sought). ↩︎
- Untapped New York, “A collection of over 350 locks inside the General Society of Mechanics & Tradesmen”, on the John M. Mossman collection and its 1928 catalogue The Lure of the Lock. ↩︎
- Stamford Historical Society, “Atlantic Street homes”, quoting Gregg D. Mecca, Made in Stamford (1984), on Henry Towne renaming the firm the Yale & Towne Manufacturing Company in 1883. ↩︎
