This is what I have from the Donnell binder. At the top of the page 7 for Nat Donnell, son of Thomas II, who died at Bath, ME 1761 is "ME Hist. Soc. Coll. II published 1847.Pages 189-228.See page 205"
"To distinguish between Nathaniel, son of Thomas and Nathaniel son of Samuel, the former was called Captain Nathaniel, Senior, while the latter was called Colonel Nathaniel, Jr. The latter had also been a captain, both on land and at sea, but he was not a colonel until so appointed during assembly of forces for the Louisburg Expedition in 1745.Care must therefore be taken in study of records before 1745,-remembering that Captain Nathaniel had wife Elizabeth;, Colonel had wife, Hannah."
On page 13 of the Donnell binder for Nathaniel Donnell 1689-1780, son of Samuel II 9:The reference is New England Miniature.A History of York ME, George Ernst.
"After Louisburg 1745 and especially after Seven Years War 1756-1763, he (Col Nathaniel emph. mine )identified himself more deeply in York affairs."
Belinda daughter of Ken/Harry/Elmer/George/Henry/Tim/Nat//Nat/Sam/Henry