Allgood publicly accused the landlord of cheating him, and threatened to ruin him, resulting a feud between the two, partly inflamed by Ann's defence of her husband. In late 1745 the Cooks moved from the Black Bull to Morpeth, Northumberland, where they ran the Queen's Head inn on behalf of the landlord, Thomas Pye. To secure their position, they entered into a bond of £369 with Pye. What the Cooks did not know was that Pye was a cousin of Allgood; in 1746 Allgood accused Cook of being a crook and a Jacobite—the Jacobite rising of 1745 still continued and was causing fear and panic in many parts of northern England. The persecution continued in 1749 when Pye instigated a rumour that because the Cooks were selling their household possessions, they were insolvent and on the verge of abandoning the town. In reality they were giving some of their unneeded possessions to their eldest daughter who had recently married and was running an inn with her new husband in Newcastle upon Tyne. By this stage the Cooks had paid back £320 of the £369 bond, so they sold much of their remaining goods and also moved to Newcastle with the intention of setting up a pastrycook shop. They were followed by their creditors for the balance of the bond, and who would not allow any terms of easy settlement; John was taken to a debtors' prison within a month of their arrival in the new town. Nothing further is known of John Cook. According to Gilly Lehmann, Cook's biographer for the "Dictionary of National Biography", it appears that in order to earn money, Cook wrote "The New System of Cookery", which was on sale by February 1753. The title page of the work stated the book was "sold by the Author, at her House in the Groat-market" in Newcastle. When the work was published in 1754 it was under the title "Professed Cookery". This also contained a poem and an "Essay upon the Lady’s Art of Cookery"; both the poem and essay were an attack on Allgood's sister Hannah Glasse, who had published a cookery book, "The Art of Cookery Made Plain and Easy" in 1747; the work was a best-seller and made Glasse one of the best-known writers of the time. Cook's criticism covered 66 pages of the work; one part of the poem, accusing Glasse of plagiarism, reads:    While the attacks on Glasse were described by the historian Madeleine Hope Dodds as a "violent onslaught", and by Lehmann as "appalling doggerel", much of Cook's criticism about the recipes and treatment of food is warranted.