the shotgun had been ground off, investigators sent the gun to forensic scientist timothy duerr. he knew that scratch marks usually weren t as deep as the original engraving. the serial number may only be a few thousandths of an inch, but the compressed metal goes a lot deeper into the metal. to restore the serial number, duerr applied an acid solution which only works at one level and goes no deeper. it will actually eat away and you can actually burn past the point of compression. it reacts differently between the compressed and uncompressed metal. the compressed being the serial number. the acid solution removed the top surface, leaving the bottom, or compressed metal, virtually untouched. upon utilizing an the restoration techniques on this shotgun, i was able to restore five of the eight digits in the serial number. those restored were l3145.
and added an acid solution to dissolve all of the organic material. what was left was primarily sulfuric acid. in a process called colorimetric testing, he added hydrochloric acid and zinc to the mix. as it bubbles through this device, the arsenic will react and form if it s present a purplish violet color. the more arsenic present, the stronger the more purple the color is. rod mccutcheon s chemical cocktail made frenss forensic history. the solution turned a deep purple. conclusive proof of the presence of arsenic. the depth of color in the reaction showed that cordelia norton ingested a massive amount of arsenic. the test results on catherine s ashes were inconclusive. nevertheless, their deaths were ruled homicides.
virtually nothing remains. it takes a lot of temperature to reduce a body to nothing but a little pile of ashes. investigators called laboratories and universities around the country, but no one knew of any way to test cremated remains for forensic evidence. but rod mccutcheon, a toxicologist at the texas department of public safety crime lab, was willing to try. so i started thinking about the possibility of detecting arsenic in a cremated remains sample, and decided it might be possible. there were a lot of things to consider. mccutcheon knew that arsenic is actually a metal and some metals survive fire and intense heat. you may change its form from a solid to a gas but you aren t going to destroy the arsenic itself. so he took the sisters ashes and added an acid solution to dissolve all of the organic
the shotgun had been ground off, investigators sent the gun to forensic scientist timothy duerr. he knew that scratch marks usually aren t as deep as the original engraving. the serial number may only be a few thousandths of an inch, but the compressed metal goes a lot deeper into the metal. to restore the serial number, duerr applied an acid solution which only works at one level and goes no deeper. it will actually eat away and you can actually burn past the point of compression. it reacts differently between the compressed and uncompressed metal. compressed being the serial number. the acid solution removed the top surface, leaving the bottom, or compressed metal, virtually untouched. upon utilizing restoration techniques on this shotgun, i was able to restore five of the eight digits in the serial number. those restored were l3145.
degrees fahrenheit for up to three hours. virtually nothing remains. it takes a lot of temperature to reduce a body to nothing but a little pile of ashes. investigators called laboratories and universities around the country, but no one knew of any way to test cremated remains for forensic evidence. but rod mccutcheon, a toxicologist at the texas department of public safety crime lab, was willing to try. so i started thinking about the possibility of detecting arsenic in a cremated remains sample, and decided it might be possible. there were a lot of things to consider. mccutcheon knew that arsenic is actually a metal and some metals survive fire and intense heat. you may change its form from a solid to a gas but you aren t going to destroy the arsenic itself. so he took the sisters ashes and added an acid solution to