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Spy Museum

This new page is dedicated to showing site visitors items and techniques used by Spies of various persuasions during WW2 and Cold War Years. Where possible images will be displayed along with descriptions of how various items were used.

I have been amazed at the simplicity and ingenuity of those incredibly smart people that thought up and developed some of these outstanding technologies and techniques.

Iodine Vapour, Secret and Indented Writing

Let's start the ball rolling with an image of a handkerchief, above, that contained secret writing and which was apparently taken from a German Uboat commamder, U234, in 1945. This particular handkerchief had been treated with iodine which clearly shows up the secret writing in code I believe. The correct term for this form of writing is 'Indented Writing' similar to that found on the Somerton Man Code page where the SA Police, using a UV light, discovered impressions on the back page of the copy of the Rubaiyat, they then used a recover ytechnique to lift the images of the writing so that they were visible. Iodine Vapour or other lifting technique was very probably used.

George Dasch Case

Two 4 man teams landed by U Boat in 1942

Chemical Reagent Technique

George Dasch's Handkerchief
Using Iodine Vapour to recover secret/indented writing was one method but when Iodine failed then other methods provided the solution. Take the George Dasch spy case in the US in 1942 two 4 member teams of German saboteurs were landed by submarine, one team, led by George Dasch, landed at a place called Amaganset, Long Island on June 12th. 1942 and the second team landed at Ponte Vedra, Florida 5 days later. Each team leader had been given a white linen handkerchief on which had been written in secret ink, the names and addresses of Nazi sympathisers in the US. The secret ink used was Copper Sulphate. The FBI agent concerned with the search for messages that the saboteurs could be carrying, examined the handkerchiefs in normal light and could see no trace of writing thus if there was anything there, it wasn't of the indented type. When subjected to Ammonia fumes, a chemical reaction resulted in the contact names and addresses becoming visible. It is possible that the techniques used was weighted pressure applied to the handkerchiefs which would have been laid on top of a surface, possibly paper, that contained the names and addresses written in copper sulphate. The pressure resulted in the transfer of the information from the paper to the handkerchiefs without leaving any indentations. Some years after the Dasch case, a similar method was used in the Colepaugh and Gimpel spy case only this time it was to be used to send messages back to Germany via fake letter drops in Spain and/or sent to name American POWs held in Germany.

Fingerprinting techniques

Using fingerprints as well as Indented writing recovery techniques was an essential aspect of finding and succesfully prosecuting espionage agents. In this video taken in 1948, a US Police officer is seen 'dusting. a car dash to recover fingerprints after which he photographs them. There is a serious question related to the Somerton Man case as to why the only fingerprints taken were from the man himself and not from any of 14 or more items that could have been treated/dusted to reveal fingerprints:


Fob Watch encoder & Other Examples

This is a fob watch encoder, not the sort of thing that an agent would necessarily carry around but maybe a handler would.

Extremely well made and as good looking as any fob watch, this kind of instrument saw lots of use and action during both World Wars.

There are similar devices that were used and hopefully we will be able to bring more images of some of the more inventive and readily concealed versions before too long.
 This is actually one of a pair of signal disks carried signalers, it is a prompt and reminder of the various common codes. Not hard to envisage a miniature version custom made for agents in the field and the hunt is on.
This is a Wheatstone Cryptograph, WW1 vintage. The device itself was invented in the 1960's and was used through both wars.

Miniature Cameras

This is a miniature camera from the WW2 and cold war years, American in fact. For it's time it was very advanced and proved to be very effective in the filed.

Light weight, very small and relatively easy to conceal from a normal cursory search, an excellent piece of tradecraft.

Whilst such tools were very useful they were of course also a liability, being found with one of these was tantamount to a potential death sentence.

Onto something a little more lethal in nature, a concealed 'sleeve' dagger used by SOE and OSS operatives.

Many of these weapons were made in Sheffiled UK and then finished in the US by Military Manufacturer John Ek.

Sleeve daggers and similar items could be sewn into clothing or strapped to your arm and were an ideal surprise weapon for use in close combat situations.

This is a particularly clever instrument, it's a shoe dagger:

You'll notice how this weapon has been carefully crafted to fit within the sole of a normal shoe, easily detectable in this day and age but at the time it would not have been an easy matter and by the time the would be discoverer found it it may have been too late.

Worth considering is that many of these weapons would have been tailor made to fit particular sized shoes and no doubt male and female.

And one more example, this time of a lapel knife, for the sharp eyed, the scabbard image is of a 3 inch lapel knife whilst the blade is of a 5 inch version, you should notice the difference in the handles:

This piece of SOE weaponry, as the name suggests could be sewn into the collar of a suit jacket or dress for that matter. Considerable damage could be done by this item when used by a trained operative.


  1. GC, with regard to the miniature camera, how many photographs per cartridge?

  2. Pete: The Minox of the same era had 16 pics, this one differs in that it was also a movie camera so I have no quick answer. Here's a better image to view:

    You could try the guys at Herberton Spy Museum near Cairns:

    They have quite a range of cameras and a lot of knowledge of the craft.

  3. .. thanks Gordo, and now a question; would I see a code on each photo, if I was examining the negs?

    1. If you were examining the code page then you would look at both positive and negative views of the image and would see whatever the camera had captured. Specifically on the code page there are numerous instances of number sets and letters in various locations. Part of the process is to look at each letter from different angles and in both views. I print out a high res image for each and then put them under a 10X magnifier with backlight to see just what the camera caught. If when you change from positive to negative the markings first noticed disappear then what you observed in the first instance is very pobably a digital artefact.

      I hope I'm answering the right question here, if not please repost and I'll do my best.

  4. not quite, I meant the negative exposures in the miniature camera's cartridge of 16

    1. Then answer would be yes if you had taken a picture of some code, you get what the camera captures even though the negs would be quite small, they would be of reasonable definition.. Sorry if I am not following your line of thought.

  5. Wasn't there something I'd guess similar to the Sleeve dagger in the briefcase found in the train station?

    [A new twist in the case occurred on 14 January 1949, when staff at Adelaide Railway Station discovered a brown suitcase with its label removed, which had been checked into the station cloakroom after 11:00 a.m. on 30 November 1948.[32] In the case were a red checked dressing gown, a size seven, red felt pair of slippers; four pairs of underpants, pyjamas, shaving items, a light brown pair of trousers with sand in the cuffs, an electrician's screwdriver, a table knife cut down into a short sharp instrument, a pair of scissors with sharpened points, and a stencilling brush, as used by third officers on merchant ships for stencilling cargo.] -Wikipedia

    1. Aseer, There were many items in the suitcase which could have had additional uses and the sharpened knife would qualify for that. As you dig deeper into this you will find inconsistencies well above the norm. Thanks for your comment, look forward to hearing more from you.