Which method first reported the use of magnetic fingerprints?

The use of magnetic fingerprints was first reported by H. MacDonald. This method involves using a magnetic powder that adheres to the fatty residues found in latent prints, allowing for the visualization and collection of the prints on non-porous surfaces. MacDonald’s pioneering work introduced this innovative technique, highlighting its effectiveness in enhancing fingerprint retrieval compared to previous methods.

The other options focus on different methodologies for developing latent prints. The Superglue Method, also known as cyanoacrylate fuming, involves fuming an object with cyanoacrylate vapors, which adhere to the moisture and lipids in the print, creating a visible impression. The Fuming Gun Method is a variation that delivers cyanoacrylate in a more directed manner to improve clarity and detail in collected prints. The Ninhydrin Method primarily targets amino acids in prints found on porous surfaces, resulting in a color change that reveals the print. Each of these methods has its own utility and application, but none were the originators of the magnetic fingerprint technique that H. MacDonald reported.