Cryptanalytic Challenge

We will be posting cryptanalytic challenges, including "tools" of the trade, on this link.  All visitors are invited to provide any solutions to the challenges or information on how a tool was used by cryptographers.  A summary of information received will be posted under the article.  Unless noted otherwise in the article, submit your comments to, with a subject line of:  Cryptanalytic Challenge -- Attn:  Dave D'Auria.

Mystery of the Symbols on Stained Glass Windows

     The symbols such as the ones shown here and provided below are some of those that are on the stained glass windows of the Memorial Chapel located on the grounds of Lake Junaluska in the western mountains of North Carolina.

      Lake Junaluska is a Conference and Retreat Center owned by the Southeast Jurisdiction of the United Methodist Church. Memorial Chapel was conceived by Dr. Elmer Clark and Bishop Harrell as a fitting Memorial to the men and women of the Southeast Jurisdiction who served in the military during World War II. It is a memorial to those living, as well as those that lost their life, in defending out way of life
     The Chapel was constructed in the late 1940s and the windows in the Main Chapel were dedicated on July 22, 1950. The Room of Memory was dedicated in July 1954 and the style of the symbols is markedly different in those windows than they are in the Main Chapel. The Room of Memory is connected to  the Chapel by a covered breezeway and contains a large notebook with the names of over 90,000 veterans from the Southeast Jurisdiction.
      All the windows were built by a company in Chicago, Ill., Giannini and Hilgart (spelling questionable). At the time the windows for the Chapel were built, the company had hired a number of immigrants from the Ukraine and Poland. One of those was Lubomyr Wandzura who worked as a Glass Painter for the company. He later purchased the company.
     His family noted that every window made was placed in a stand in the front of the shop where the early morning sun would light its panes and parts.  There, the balance of the various panels and colors of glass would be checked to see if they were acceptable. They also remarked that none of them ever saw symbols such as those below in any other windows that were made by the company. They even contacted a retired stained glass artist from the shop and asked her about such symbols. She had never seen anything like them.
      In correspondence with a stained glass artist, none have seen such symbols. They are quick to point out that artists use "doodles" to balance the light of the various panes but had not been able to provide a real example as to when that was used.
      These windows are unique and were built by persons who knew the windows were going to be installed in a Memorial Chapel. The symbols are far too complex to be artist "doodles" and had a special meaning to those that put them there.
      We owe the remaining WWII veterans an explanation of the symbols and their meaning and we hope someone out there will have some answers.  It is the least we can do for the greatest generation.

      For more information about the Lake Junaluska Conference and Retreat Center and to see more images of the stained glass windows visit John Hoopers blog on the Memorial Chapel.

Note: The images below were “cut” from some of the images of the stained glass windows. If you would like to receive more images of the stained glass windows on which these symbols appear visit the Memorial Chapel Blog.



 Comments on the window symbols by Kent - received 1/26/14)

I am by no means an expert on any of this but I would like to suggest that these symbols may come from the Ukrainian Pysanka tradition. I was not able to find any example of these on stain glass windows but they are very common on, for example, Ukrainian Easter eggs. Similar traditions exist among other Eastern European countries. I noted that a number of the workmen involved in the project came from these countries. The meanings of the sysmbols appear to be quite ancient but there are adaptations to Christian beliefs. Certainly many churches engage in the tradition. One thing that may throw people off track a little is that Pysanka is often, but not always, very colorful which in this case probably would have disturbed the balance in the windows.
I have enclose a number of Pysanka pictures which show symbols identical, or nearly identical, to many of the symbols and patterns on the windows. It also seems possible that the very window design itself divided into the many triangles, wedges and diamonds may come from this tradition. I enclose a link to an interesting Wikipedia article. Note the discussion of 40-48 triangles and wedges. Some images from the Wikipedia article are provided below.
In the picture Pysanky Spirals and Plants (far left in the row of pictures) you can see a good example of the brown spiral design against black background, on the brown/white/black egg that matches the spiral on the window pretty well. This design is said to represent protection against the evil spirit. The next egg has a plant design with inwardly curling stalks which matches one of the plants on the windows pretty well (window with red cross). Plants appear to be for good harvests or represent the natural environment. There are a variety of other plant designs on the windows, water designs (said to be for rain and good harvest) that can be found on the pictures and many more can be studied on the internet.
Another picture shows an example of the "crossed clubs" design, and in some of the other pictures you also see good similarities with the window designs of crosses, so called "eternity bands" for an eternal life etc.
All of this is of course very much the theories of a non-expert and should be verified with a Ukrainian/Pysanky specialist, but it appears to me that the window artists sent a final greeting from the very depth of their homeland traditions and endeavored to provide a place full of natural goodness and spiritual protection. That seems entirely in keeping with the place.


 I realize after sending the above that I forgot to include a picture I found perhaps providing the "code sheet" for the little colored wedges on the windows

Kent has updated his finidings (posted 2/2/14)

In his recent email, Kent provided side-by-side comparisons of Junaluska Chapel Window symbols matched to Ukrainian Pysanky and related symbols.  You can get his complete submission as a PDF by clicking on Grouped comparison


We are looking for information from any of our web site visitors who may know who, how, when and where this device was actually used by cryptographers, radio operators or other NSA/DoD personnel.  The DoD transfer form attached to th e unit describes it as a "National Security Telephone".

The artifact pictured is believed to be a 1950s era predecessor to today's modern secure phone system. It carries an NSA label of CE 62603 Subscriber Set No 1094, which designates it as "Communications Equipment" (CE) vice "cryptographic equipment" (KL). This subscriber set uses vacuum tube technology and may have been connected to a stand alone voice encryption device such as an early KY-3 or KG-13/HY-2 secure voice system. In tandem, it likely provided secure encryption for voice communications between facilities. The "CE" nomenclature was a designator often used by Bell Telephone and the DoD/US Army for their systems, which may point to the origin of this subscriber set. This particular set, in private hands, was shipped from an Army MARS Radio Station in Fredericksburg Texas to Kelly AFB is San Antonio. It may have been released from DoD inventory in 1974. We have a similar set in our Museum inventory with no other clarifying information.

The unit itself appears to be heavy gauge cast aluminum. The top has a carry handle/latch that when elevated & rotated loosens and removes the bolt that secures the top to the base. The interior is a heavy black plastic base with a center raised console. There is a a small speaker above the handset cradle. The handset is heavy black plastic with a conventional coiled cord that is connected to the left side of the console with a heavy duty mil-type Cannon/Amphenol-type connector. On the right side of the console is a phone jack. On the front of the console is a push-button labeled CALL and to its right is a black knob labeled VOLUME. The only possible external connection (perhaps to a stand alone encryption device) is a hole in the center of the bottom of the phone base.


The artifact pictured below is believed to be a WW II era Slidex code device. A Slidex is a manual encoding system used mainly for tactical communications to provide a short-term level of security when non-secure communication links are being used. They use a word or sometimes phrase substitution based upon a prearranged set of codewords or codephrases. The device pictured below came from the Lou Kruh collection donated to the NCM in April, 2010. It is about 8inches long by 4 inches wide. A wheel on the side rotates (i.e., "slides") the list of codewords forward or backward to encrypt usually short stereotyped messages. We are looking for information from any of our website visitors who may know who, how, when and where this device was actually used by cryptographers and/or radio operatiors.  

Comment by Dave on 10/21/10

The Slidex with which I'm familiar was a WW2 British tactical cryptosystem for tactical operations, regiment and below, combining the features of cipher and code, with the code vocabulary peculiar to intended service (staff, signals, supply, transportation, etc.). Probably from their Free French association with the Allies in WW2, the French in Indochina passed the system to their allies there in the 1950s, and it was known to the opposition. In the form with which I was acquainted, see

What you have pictured from Lou's collection appears to be more along the lines of a "handy-dandy" for radio/telephone operations than what I understand as the SLIDEX system per se. There is a website for WW II reenactors from Wireless Group Set19 that seems to have some restricted distribution stuff available on limited basis to its membership, but other SLIDEX references can be found using a Google search.

Comments by Adam on 10/19/11

I can tell you this, from what I've read each day had a 'code' setting which was different for each division, and everyone (at least, most officers and signals personnel) in the division knew on each day what the settings would be for that day, and presumably for the next couple days. My guess is that these devices generally accompanied signals personnel and would have been fairly common in headquarters and observation posts.

So far, I've only seen one 'primary source' discussion of how this was used, and it comes from the 1st Division AAR for August 9th, 1944 (see photo of AAR below).  A single American platoon at St. Loup (northeast of Mayenne) came under heavy attack and was forced to retreat. Apparently, the Slidex device was left behind and captured. Therefore, the division abandoned the Slidex settings for August 9th and 10th, and shortly before midnight all the subordinate formations were ordered to use the August 11th setting for the remainder of August 9th and August 11th.

So I think you will agree that at least this single source suggests two things: one, the Slidex was a tactical device likely to be seen at the tactical level, and two, its settings were generally determined by the division on a daily rotation.

1st Division AAR, August 9th, 1944


The 10 Point Divider (sometimes called an 11 Point Divider) pictured below came from the estate of a now deceased former cryptographer.  In the public sector this "tool" is commonly used in drafting, form and textile design, model design, long range navigation, etc. We're looking for information from any of our web visitors who may know how this tool was used by cryptographers.

Comment by George on 5/16/10

The divider, and others like it (I have one) were used to manually transcribe data (1's and 0's) from analog displays and was used by both signals analysts (to find structure) and cryptanalysts (to obtain cipher). Time base jitter was a common problem and the higher the data rate, the more uncertain one was of the integrity of the stream. Use of these dividers often meant the difference between "no cipher" and "some cipher" until a system could be devised to automatically digitize the data.

Comment by Frank on 7/13/10

I used the 10 point divider in the 1960's in a signal analysis application to determine
presence of and to measure cyclic activity on continuous paper sonogram
displays. The 10 point divider came in different sizes from about 8 inches
in length to about 12 inches. In later years it became a handy tool to lay
out distances to scale on maps. This instrument may still be on display in a
corridor display case on the fifth floor on building 2A.