The following description is quoted from [Tonkin 1739] and must be read in the context of that date. The extract is taken from [Polsue 1868]. Other extracts are available online.
Lanistley manor extendeth throughout the parish of Gulval from the Moreps to the Gundrons; that is to say, from above the sea to the Down Hills; it extendeth also through a part of the parish of Ludgvan.
At Kenneggy is the dwelling, by lease (the fee being in his elder brother, William Harris of Hayne, Esq.,) of Christopher Harris, Gentleman, an attorney-at-law, who married a daughter of John Foote, of Truro, Esq. His elder brother, who married the daughter of John St. Aubyn, Esq., of Clowance, in the parish of Crowan, is now in possession of Hayne, near Lifton, in Devonshire, having succeeded to it on the decease of Sir Arthur Harris, jun., the last heir male of the elder branch. On removing to Hayne he leased Kenneggy to his younger brother aforesaid; who, by reason of the elder brother’s yet want of issue, is likely to become his heir. The arms of Harris are, Sable, within a bordure three crescents Argent.
Mr. Edward Llwyd, in his letter to me, would have this parish to take its name from the inscription on the stone in Maddern parish, “Riolabran: Cunoval: Fil:” and that Cunoval is turned by corruption into Guloval, for that he found many such instances in Wales.
I should be glad to agree with so great a critic, but since there is a saint, or bishop, whose name comes very near to this—S. Gunwall, whose memory the church celebrates on the 6th of June, I cannot forbear fancying, especially the humour of the country being considered, that he is the patron and the namer of this parish.