Student received the highest score, instead of passing the history test ninja clean sheet

Japanese freshman Amy Haga (Haga Eimi), which was given the task to write an essay on the history of the ninja and passed the Professor a blank sheet of paper. Despite this, it received the highest rating. A specialist in medieval masters of disguise appreciated the efforts of his pupil, who managed to make writing invisible ink that appear when heated.

19-year-old Aimee used the ancient Japanese method of cryptography "by aburizal", which was previously used for the compilation of spy reports. To do this, the girl had to find in books recipe for a special ink made from soy beans and produce them, strictly observing technology.

For the preparation of "aburridas" Amy Haga soaked soybeans overnight in water, and in the morning wring them through a cloth. The substance is a student of the spread to the desired consistency with water and used as ink. In order to comply with historical accuracy, meticulous Aimee wrote the characters with a thin brush on rice paper called washi, which is used in Japan for many centuries.

Feature soy ink is that once dry they become completely invisible. To read the text written "aburridas", you need to heat the paper over a flame. After that it becomes clearly visible brown text.

Aimee wasn't sure that the teacher will understand what constitutes a clean sheet, so before the delivery of work attached to it the usual note with a note "Heat it." The Professor held up the paper from the heating convector and saw the body of the essay that led him into raptures.

The student achieved their goal and received the highest rating. Journalists on the BBC about how she came up with this unusual idea, Haga says:

To write an essay about ninja freshmen history teacher asked after visiting the ninja Museum of the city of IgA, in mie Prefecture. This Museum, unique in the world, located in the Central part of the Yoke-Ueno and is a small medieval castle in the Middle ages belonged to the clan of spies and secret assassins. In the exposition of ninja weapons from different eras, as well as their clothing and lots of clever adaptations that help them to become invisible, to penetrate into the most impregnable fortress.