"Jack is greatly improved, but bites now & then as Yr Lp may remember he could when you was here. The battles between him & my Boy Gaetano (whom you may remember to have a St Januarius, a I.C., & a Pulinchinello tattoed on his arm on his arm) when he is naked & going into the Sea with me in the morning are really curious. He never bites him but play him all sorts of tricks, his favourite one is to pull him by his --- & then he always smells his fingers; the other day he pull'd rather hard & the boy clapped his two hands upon it whenever the monkey approached. Jack made use of a most excellent expedient to put the Boy off his guard. He passed by him & kept his hind parts close to the Boy who was setting at the head of the boat, & who no longer feared him removed his hands; Jack who was squinting back immediately seized his pray with one of his feet, which you know are equally handy, & held him fast to the great entertainment of the Watermen & myself."
British Envoy to Naples at the end of the 18th century, volcanologist and antiquities expert Sir William Hamilton (1730-1803), wrote of his mischievous and excitable pet monkey Jack in 1779. Excerpted from FIELDS OF FIRE: A LIFE OF SIR WILLAM HAMILTON by David Constantine, Weidenfeld and Nicholson, 2001.

Jack on His Deathbed
1780 - Favourite of the Hon. W. Hamilton - His Britannick Majesty's Envoy Extraordinary and Plenipotentiary At The Court of Naples.
The Liontailed Macaque