The discussion can be approached using the Special Operatives Executive (SOE) properties for ‘ideal’ invisible ink as the evaluation criteria.

Invisible Ink Pens - Etsy UK Invisible Ink Pens - Etsy UK

It is 410BCE and the Ionian (or Decelean) war, between Athens and Sparta has been raging for four years. You have been tasked by King Agis of Sparta to develop a way of delivering secret messages to his armies, which would be unreadable if they fell into the enemies’ hands. You wonder if there is a way of writing with an ink that is only visible under certain conditions. Like all good science-artists, you decide to investigate further… Lemons were also used as organic inks by Arabs around 600 AD, and during the 16th century in Europe. [6]asking questions and develop a line of enquiry based on observations of the real world, alongside prior knowledge and experience; M iron sulfate IRRITANT, developed by 0.1 M sodium carbonate, 1% starch solution (e.g. corn starch or potato starch), or by 0.1 M iodine solution An E2E voting system called Scantegrity II uses invisible ink to enable the voter to obtain a confirmation code only for the voted selection. [10] Properties of an "ideal" invisible ink [ edit ] comparing and grouping together everyday materials on the basis of their properties such as solubility and transparency;

Invisible ink - Wikipedia Invisible ink - Wikipedia

Wheeler, Jo; Temple, Katy (2009). Renaissance secrets, recipes & formulas. London: Victoria and Albert Museum. p.98. ISBN 9781851775774. Former MI6 agent Richard Tomlinson stated that Pentel Rolling Writer rollerball pens were extensively used by MI-6 agents to produce secret writing in the form of invisible messages while on missions. [21]Many of them work as pH indicators, so when in doubt, paint or spray a suspected message with a base (like sodium carbonate solution) or an acid (like lemon juice). Equipment: Some inks glow faintly or fluoresce when under an ultra-violet lamp. This is a property of many substances, particularly organic substances and body fluids. A coded letter from Benedict Arnold, originally written in invisible ink. Handwriting by Peggy Shippen Arnold is interspersed with coded communication in Arnold's hand. Giovanni Battista della Porta is credited with the first recipe for a sympathetic ink, derived from alum and vinegar, as well as the first book on secret writing and invisible inks, Magia Naturalis (1558, 1589). [8] [4] :24 Since then, a wide variety of invisible inks have been used for all sorts of secretive purposes. A formula similar to oak gall ink was created by James Jay and used by George Washington and the Culper Spy Ring during the American Revolution and lemon juice was used by the 'Lemon Juice Spies' (Carl Muller and 4 other Germans, who all died for their efforts either by suicide or execution, along with John Hahn, an English baker) during World War I. [6] [4] In World War II, neutral or acidic solutions of phenolphthalein, a chemical compound extracted from pills for constipation, were used as invisible ink. [9] It is colorless but turns pink when exposed to alkali such as ammonia and bicarbonate soda. [9] General application and use [ edit ]