Hall's Safe & Lock Co, Cincinnati, Ohio - 1 mvt. w/ Chronometric Time Attachment

Back Up Next

This example has an engraved geometric-patterned front movement plate that may be unique to this lock. The interior of the door is also engraved. The dial bezel also is embellished with a wave-pattern engraving; something not seen in other locks from this company with the exception of one other lock that that was used as a exhibition piece by the Hall company. (1) This lock, however shows ample signs of wear from use within a working safe door. Hall's serial numbering for their single movements began with 2001, making this an early example. It is almost certain that Hall did not make all of their early serial numbered single movements in this style since only three are currently known. Most of the others would have been intheir conventional carriage clock style of escapement. 


The first photo shows a better view of the front plate engraving. Next the engraving on the door interior.


The spring barrel wheel also has a decorated pattern on its rim. The decoration is probably unique to this lock since it would not otherwise be able to be seen in the company's other locks. It is the same pattern seen on most of the Hall and Consolidated lock aperture window frames. The example shown is not from this lock but another single movement Hall lock. All of the other locks made by this company used a platform escapement mounted on top and between the movement plates just below the aperture window to allow the user to verify the movement was running.


Here is a close up view through the unique cut-away dial. The balance wheel can be easily seen through the front opening. One can also see the balance wheel rate adjustment pointer in the upper left hand corner. The aperture window in this lock case has a different engraved pattern than seen in most other locks. This aperture window cannot be used to verify the movement's running is is probably there because the prototype movement was mounted into a regular single movement case.

                                                                                                                    The Chronometric Time Attachment


These as well as the following photos show the action of the "Chronometric Time Attachment". The language actually is nonsensical, but sounds important. What I believe it refers to is a mechanism that allows to lock to be opened in case of failure of the movement. This is important since there is only one movement in the time lock. The first photo shows the area where a locking pawl is located within the wheel train, it is currently in the disengaged position. Next a close up through a 30x glass showing the pawl engaged into the teeth of the fourth wheel in the movement train.


The first photo shows the locking pawl described above just under the second wheel in the movement train. It is attached to a lever, (3) that is positioned approximately 900 to it and is pivoted where they join together. The next photo shows where a large pivoted lever, (1) contacts the lever attached to the pawl, (3). Part (2), is what connects to the combination lock's fence. When the lock goes on guard this part raises the fence and disables the combination lock preventing anyone from dialing in the combination until the time lock goes off guard. In the case of the time lock failing, the bolt work can be manipulated to pull the fence holder (2) slightly downward, not enough to allow the fence to engage the tumblers, but enough to rotate clockwise the large lever (1), to which it is connected, about 300. When the bolt work is released a bias spring rotates the lever (1) back to its original position. The repeated action causes lever (1) to rotate back and forth; pushing the lever (3) to the right, a bias spring brings it back to the left causing the pawl to advance the fourth wheel in the train and over time the main wheel to slowly rotate counterclockwise to the point where it would count down to zero. The lock would then go off guard, allowing the fence holder (2) to lower the fence toward the tumblers, enabling the safe to be opened.


However, if someone were to try to use too much force on the bolt work, or attempt to manipulate the rocking too fast, say in the case of a robber trying to open the safe in the middle of the night, the large lever will turn further than 300 and lock onto the pawl lever as shown. This permanently locks the pawl against the teeth of the fourth wheel. This would permanently disable the lock preventing further tampering. I'm not sure how wise this feature is given that once locked, it appears to be impossible to release from the outside. There may have been some other unknown auxiliary mechanism to do this, but I do not know of any.

The advertising sheet shows a single movement time lock in the larger case format and must have either been a very early concept model or prototype. It has the rectangular window aperture on the top of the case which was replaced by the round port hole windows within the first year of production, in late 1876. It also appears to have a bolt dog arrangement rather than the drop down attachment to the combination lock's gate. There is no opening in the case bottom for this attachment. The interesting thing about this advertisement is its use of the term "Chronometric Time Movement and Attachments". Similar to that on the dial of this example having "Chronometric Time Attachment". Within the body of the ad is described an apparatus within the lock that will allow the owner to bypass the movement if it fails. Which may be what the company is referring to as the chronometric attachment, but this is only conjecture at this point. I have not seen the term used on the dial of any other Hall or Consolidated time lock nor have I seen the bypass feature.

This video shows how the Hall and later Consolidated Time Lock company's time locks operated. These functioned differently from most other time locks in that they operated directly upon the combination lock mechanism rather than upon the bolt work within the vault door.

What is not mentioned in the video and was discovered after its completion is that in addition to the anti-tamper feature is the fact that the same mechanism can be used to bypass the lock in the case of the failure of the clock movement. Hall called it the Infallible Lockout Protection system. This is critical because there is only one movement offering no redundancy in the case of failure. This was an experimental lock and to the best of my knowledge was unique. The bypass feature is not seen in any other locks by this company. Rather, in the case of a failure, the owner would call the Hall company and a "secret" combination would be revealed allowing the time lock to be bypassed and then the regular combination dialed in. Of course this is a rather unsatisfactory option since the safe can be compromised. The single movement format was soon supplanted with time locks having two or more movements to provide redundancy obviating the need for "secret combinations" or cumbersome bypass features.

This time lock as received was not functional. Click here, to see some of the repairs that were needed to make the time lock work again after 140 years.

Single movement by this company that was the predecessor of the Consolidated Time Lock Company c.1876. This was very early in the production run since Hall numbered his single movement time locks beginning with 2001. Time locks made under the Hall name are rare as this company was only in business a few years before being merged into the Consolidated Time Lock Co. in January of 1880 to insulate his successful safe and lock business from his risky and untested time lock business.(2) This movement configuration, that is without a platform escapement mounted on the top of the movement, is the only one of three currently known, see below. Hall and later Consolidated used E. Howard for their movements, but this appears to be from a different source. Case #94. Movement #2057, 3 5/8" w x 3 1/8" h x 2 5/8" d. file 201

The lock pictured below is from the John M. Collection located at the General Society of Mechanics and Tradesmen in New York City. The movement is numbered 2026 and is mounted in what is clearly a presentation piece. It is interesting that a trip lever is located where one would expect below the case, but it appears that there is also a rectangular feature on the right side of the case. This is the end of a bolt. Notice the similarity of this feature and location to the advertising sheet illustrated above which also shows a rectangular bolt in this position. The lower decorative cover of this lock is removed and the bolt is clearly visible in the photograph on page 175 in the book Lure of the Lock. To the best of this author's knowledge no other Hall lock other than this example had this bolt work feature. The illustration did not have the bottom release as this would not be needed with a bolt dogging device. It is possible that the lever on the bottom is there to demonstrate the lock.


Back Up Next

(1 and 2) American Genius Nineteenth Century Bank Locks and Time Locks, David Erroll & John Erroll, pg 190-191 and 168