n thirteenth century China, a field laborer was murdered with a sickle — and every one of villagers' sickles were indistinguishable. So the specialist had each laborer set out his device in a field, and watched that only one sickle pulled in blowflies, which were known to search out blood. Everything Worth Knowing About ... Catching a Criminal. Its proprietor, the offender, quickly admitted. The Chinese sickle killing is one of the main announced instances of legal examination. The part of science in prove gathering and introduction has just turned out to be more importan.