In 1836 the Penny Magazine published a long article on Cornwall, its occupations, housing and diet. Here’s an extract which includes some comments on the local dialect.
It is still usual to call elderly persons ‘uncle’ and ‘aunt’, and the ‘good night’ is commonly given in passing. The use of nicknames is very prevalent. These are not only personal but hereditary, and many families are distinguished by them.
Many French words, as well as terms from the extinct Cornish language, are in common use; the latter especially in terms of art among the miners. A sort of recitative or sing-song pronunciation is characteristic and amuses the stranger much. Agriculturists, miners and fishermen pronounce very differently from each other in some districts; and within ten miles all these varieties of sound may be sometimes met with. The people generally are much inclined to use the points of the compass, and the eastward, the westward, the south country, etc. are frequently heard.