this belief with his opinion that two weapons were used—one of Tabram's wounds, which penetrated the chest bone, was inflicted with a weapon longer and stouter than the others, a dagger or possibly a bayonet, while the others were inflicted with a shorter, slimmer knife. Several 20th-century psychological reports have assumed Mary Ann Nichols to have been Jack the Ripper's first victim, but add that her murder was unlikely to have been his first attack. Some have suggested the Ripper may have murdered Tabram before perfecting his modus operandi of overpowering and cutting the throats of his victims. Other researchers, however, such as Philip Sugden in The Complete History of Jack the Ripper (), and Sean Day in Peter Underwood's Jack the Ripper: One Hundred Years of Mystery (), do view Tabram as a probable Ripper victim. Sir Melville Macnaghten was only actively involved in the Whitechapel murders investigation between 1889 and 1891; thus, his notes reflect only the opinions of some police officers at the time and include several factual errors in the information presented pertaining to possible suspects. Serial killers have been known to have changed their murder weapons, but especially to develop their modus operandi over time, as the Ripper did with increasingly severe mutilations. While the five canonical Ripper murders were located roughly north, south, east and west of Whitechapel, Tabram's murder occurred close to their geographic centre. It is possible that her murder was one of the first committed by the Ripper before he had chosen his later modus operandi. In 1998 an Australian researcher, Ted Linn, produced his findings in a booklet called The Case of the Redhanded Copycat, in which he outlines his case that Martha's husband, Henry Samuel Tabram, was the real Ripper. He bases this on cryptographic clues he claims to have found in letters written by the Ripper and other evidence. See also Cold case List of serial killers before 1900 Unsolved murders in the United Kingdom Notes References Bibliography Begg, Paul (2003). Jack the Ripper: The Definitive History. London: Pearson Education. Begg, Paul (2004). Jack the Ripper: The Facts. New York City: Barnes & Noble Books. Evans, Stewart P.; Rumbelow, Donald (2006). Jack the Ripper: Scotland Yard Investigates. Stroud, Gloucestershire: Sutton Publishing. Evans, Stewart P.; Skinner, Keith (2000). The Ultimate Jack the Ripper Sourcebook: An Illustrated Encyclopedia. London: Constable and Robinson. Fido, Martin (1987). The Crimes, Death and Detection