He was the third of eight children to tailor William Richard Petherick and Phoebe Mary Ann, née Cooper who had married in St Pancras on 12 April 1835.

He married Clementina Augusta Bewley Bonny (c.1860-1909) and the couple immediately moved to Addiscombe, Surrey, where they remained for the rest of their lives.

The couple had seven children, two of whom died in infancy, leaving five girls, of whom one, Rosa Clementina (1872-1931) became an illustrator like her father.

[2] The Annual Review noted on his death that he was an artist of repute who exhibited at the Royal Academy on several occasions.

[20] By the time that Petherick published his book on Guarnerius in 1906, he was now the president of the Cremona Society, as the title page declares.

[22] He frequently provided certificates of authenticity for violins, and appeared to give expert evidence on the origin of stringed instruments.

He was known not only by a mix on anglicised and Latin forms of his name but also by the soubriquet of del Gesù (of Jesus) because he began to add a religious symbol after his name 1739.

On 4 May 1906, the member of the Cremona Society were told that there would be a special meeting on 30 May,[33] at which a paper dealing with the discovery of the only known cello by del Gesù would be read by Petherick and that the renowned cellist and teacher Herbert Walenn would play the instrument.

The August edition of The Strad reproduced a photograph of the front and back of the cello,[35] and printed a series of documents dated 28 April 1906: In his book, Petherick claimed that Andrea Gisalberti of Parma was del Gesù's master, and the certificate referred to this.

In their 1916 book, Hidalgo and Piper said that Andrea was a little-known maker of no great account and that neither Mr Petherick's arguments, nor the examples by which he strove to support them were seriously accepted by most judges of the first rank.

In the first of these cases, in 1907, the dealer Joseph Chanot relied on Petherick's certification of two violincellos to defend himself from an action by the purchaser.

Moya and Piper called the 1902 (with a 2nd edition in 1909), book by the Hills brothers on Antonio Stradivari "the most exhaustive critical survey of the subject which has yet appeared".

[50] In the second case, in April 1908, Dr. Hitchcock had bought a violin, certified by Petherick to be the work of Petrus Guarnerius, for £100.

[53][54] Chevalet's assessment was that this last trial should dispose once and for all of Mr Cooper's firm and of "the self-styled expert" Peterick.

A slim volume dated 1910, announcing the retirement of Balfour and Co. as "Antique Italian Violin Transfer Agents and Experts" was offered for sale by Cambridge Books of Maine in February 2020.