From the 1800's to 1985 describe two ways that forensics science was used to determine crime

The 1800s

In the 1800s the field of forensic science saw substantial progress. The decade saw:

- The first recorded use of questioned document analysis.

- The development of tests for the presence of blood in a forensic context.

- A bullet comparison used to catch a murderer.

- The first use of toxicology (arsenic detection) in a jury trial.

- The development of the first crystal test for hemoglobin using hemin crystals.

- The development of a presumptive test for blood.

- The first use of photography for the identification of criminals and documentation of evidence and crime scenes.

- The first recorded use of fingerprints to solve a crime.

- The development of the first microscope with a comparison bridge.

- Forensic science was significantly applied in 1888, when doctors in London, England, were allowed to examine the victims of Jack the Ripper for wound patterns.

The 1900s

Early forensic specialists were self-taught. There were no special schools, university courses or formal training. The establishment of a forensic science curricula in 1902 by Swiss Professor R. A. Reiss at the University of Lausanne, Switzerland, was one of the first steps towards establishing forensic science as an academic discipline.

It wasn't until the early 1930s that universities began offering courses and degrees in criminalistics and police science. In 1950, the University of California at Berkeley established one of the first academic departments of criminology/criminalistics, and the American Academy of Forensic Science (AAFS) was formed in Chicago.

Almost every year in the 1900s recorded an advance in the field. This century saw the:

- Establishment of the popular practice of using the comparison microscope for bullet comparison in the 1920s.

- Development of the absorption-inhibition ABO blood typing technique in 1931.

- Invention of the first interference contrast microscope in 1935 by Dutch physicist Frits Zernike (for which he received the Nobel Prize in 1953).

- Development of the chemiluminescent reagent luminol as a presumptive test for blood.

- Study of voiceprint identification.

- Invention of the Breathalyzer for field sobriety tests.

- Use of the heated headspace sampling technique for collecting arson evidence.

- Development of the scanning electron microscope with electron dispersive X-ray technology.

- Identification of the polymorphic nature of red cells.

- Enactment of the Federal Rules of Evidence (1975).

- Evaluation of the gas chromatograph and the mass spectrometer for forensic purposes,.

- Development of the polymerase chain reaction (PCR) technique for clinical and forensic applications.

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