Bronze Tiger Tally of Marquis Lin Yuan
The Bronze Tiger Tally of Marquis Lin Yuan is an artifact dating back to the early Western Han Dynasty (206 B.C.-A.D. 25). It is so tiny that an adult can hold it in one hand. The tally is in the shape of a lying tiger, with its head protruding forward and its tail rolling upwards. Square grooves on the sides verify authenticity by interlocking.
A tiger tally consists of two halves, with one half held by the monarch and the other by the commanding officer as a symbol of military authority. The officer would only accept orders accompanied by interlocking the other half.
Tiger tallies originated in the Spring and Autumn Period and were most commonly used in the Warring States Period and Qin and Han dynasties. Most were cast in bronze and engraved with inscriptions.
One can read information from the inscriptions on only one half of an early tiger tally. From the Han Dynasty (206 B.C.-A.D. 220), inscriptions were usually carved on the tiger's back separated into two halves, and the message they carry can be legible only when the two halves are pieced together, thus enhancing the confidentiality.
With nine incomplete characters on the tiger's back, this is the left half of a tiger tally owned by Marquis Lin Yuan who commanded the army. To move the troops, the emperor needed to send an envoy with the right half to the garrison of Marquis Lin Yuan, who would accept the order when the two halves matched.
The unique design and craftsmanship of the tiger tally provides valuable references to the study of the military authority system and army management methods in ancient China. It is also the physical evidence of early encryption methods in the military of ancient China, and its authenticity verifying approach is similar to modern encryption techniques.
臨袁侯銅虎符
臨袁侯銅虎符，為西漢早期制品，體量小巧，成年人一手可握。虎呈俯臥狀，昂首向前，虎尾向上卷起，側面有方形凹槽，用于對合時驗證真偽。
虎符是將完整的虎形對半分開，一半在君王手中，一半作為軍權憑證授予將領，如需調兵，要兩半合一。虎符最早出現于春秋時期，盛行于戰國秦漢，多用青銅鑄成，再刻上文字。
早期的虎符只有一半也可讀出信息，自漢代起虎符多將文字置于虎的脊背騎縫處，合符才能讀出全部內容，保密性更強。由這件虎符背上的九個錯銀半字，可知此虎符為左半部分，在統軍的臨袁侯手中。如需調動軍隊，君王須派使臣持右半虎符前往臨袁侯駐地，合符無誤即可發兵。
虎符獨特的設計和工藝是研究中國古代兵權制度和軍事管理方式的珍貴資料，同時也是中國古代早期軍事保密方法的實證，其配對驗證思路與現代保密技術有異曲同工之處。
