(EST PUB DATE) SECRET WRITING

• Document Type: CREST
• Collection: Secret Writing
• Document Number (FOIA) /ESDN (CREST): CIA-RDP11X00001R000100010002-8
• Release Decision: RIFPUB
• Original Classification: C
• Document Page Count: 1
• Document Creation Date: November 3, 2016
• Document Release Date: August 1, 2011
• Sequence Number: 2
• Content Type: REPORT

Approved For Release 2011/08/01: CIA-RDP11X00001 R000100010002-8
CONFIDENTIAL
kt:y.:tF JWED } EXEMPT from automatic declasaificcrtion
Authority O per E.O. 11652, Sec. 5(E)(2)
BY...... ...r NABS, note ..................... 141 Nam ^ - -Y Agency at-9
SECRET WRITING H4_,._.. Review
For Secret Writing can be used :
First : A solution of nitrite of seda and starch in water x
/may he carried for example in handkerchiefs or starched
collars, starched shirts or anything else starchedt -MesE
things being laid in this solution and then ironed. The
article thus treated Is later on again put in water and
a solution. obtained which can be used for invisible
writing. / The best means for devloptng are iodite of
potersiutn.
Second: Sulpha to of iron, developel preferably with ferro
cyanite of potassium.
Third: Nitrate of silver developed preferably with Us 2,
or 1t..
DourLh rice starch, developed with ink mixed. with water.
Fifth: Lemon juice, developed with Ferro cyani to of potas;
x A tumbler of water is boiled. together with a table spoon
of starch, allow to cool, and add ten gramme of nitrite
of soda.
For developing secret: writing is used:
1. Iodi to of Potaseiutr, /5 grams with 100 grams of water, 2
of tartaric acid added/
2. Sulpharated soda.
3. Ferro cyanite of potassium.
1.. Irk, mixed with water / laid on with a. brush/
/ Or
Approved For Release 2011/08/01: CIA-RDP11X00001 R000100010002-8