Serology: It's in the Blood
The Mad Carpenter
It was the brutal murder and dismembering of two young boys on the island of Rugen, off the coast of Germany, that turned the authorities' attention toward Ludwig Tessnow, a carpenter from Baabe. The year was 1901, and the two boys had run out to play. When they failed to return, a search was organized. It wasn't long before their body parts were found scattered over a wide area, and eventually the searchers located their disemboweled remains.
Earlier that day, Tessnow had been seen talking to them, and although he denied any involvement, a search of his home turned up recently-laundered clothing that had suspicious stains. He claimed that they were from wood dye, which he used almost daily in his profession. Unable to prove otherwise or to find other incriminating evidence, the police left him alone... until one investigator recalled a similar crime.
Three years earlier in Osnabruck, Germany, two young girls had been found in the woods, butchered in a style similar to the boys. The man seen loitering near the woods, his clothing stained, was Tessnow. At that time, too, he had claimed that the stains were from wood dye.
The local prosecutor then heard a farmer's report that a man who looked like Tessnow was seen fleeing from his field, and he then found seven of his sheep slaughtered. Their legs had been severed and tossed about the field. Tessnow was brought in for a line-up and the farmer had no trouble picking him out as the man who had run from his field.
Still, the police needed better evidence to tie Tessnow to the murders. Then they heard about a test recently developed by a biologist, Paul Uhlenhuth, that could distinguish blood from other substances, as well as mark the difference between human and animal blood. Tessnow's clothing was given to Uhlenhuth for thorough examination and his conclusions marked a turning point in the history of forensic science. He found dye, but he also detected traces of both sheep and human blood.
With this evidence, Tessnow was charged, tried, convicted, and executed.
Shortly thereafter, forensic blood analysis began to progress rather rapidly in several directions.