@danetyghe1 's discussions as @Motherfocloir last week where he compared the Irish & Welsh languages led me to muse a little about Cornwall and the Cornish Language

Nuair a bhí Dane mar choimeádaí ar Motherfoclóir an tseachtain seo caite. Do labhair sé an chomparáid idir an Ghaelainn & an Bhreatnais. Chuir sé sin in aigne dom beagán smaoineamh a dhéanamh fé Chorn na Breataine & an Teanga Coirnis

Cornwall (Or Kernow in Cornish) is one of my absolute favourite places on Earth. It has its own language distinct from English which is recognised as one of the Celtic languages. This language is known as Kernewek. It is a P-Celtic Brythonic language similar to Welsh & Breton

Tá Corn na Breataine (nó Kernow) ar cheann de na háiteanna is fearr liom ar an Domhan. Tá a theanga féin aici a aithnítear mar cheann de na teangacha Ceilteacha. Tugtar Kernewek ar an teanga seo. Is teanga P-Ceilteach Brythonic í atá cosúil leis an mBreatnais agus an Bhriotáinis

Cornish was recorded as extinct following the death of the last native speaker, Dolly Pentreath in Mousehole, 1777. However many dispute this extinction citing speakers following her death throughout the 19th Century, all the way up to the Revival in the 20th Century

Taifeadadh gur imigh an Choirnis as feidhm le bás an chainteora dheireanaigh, Dolly Pentreath i Mousehole, 1777. Mar sin féin, easaontaigh alán daoine le sin, dúradar go raibh cainteoirí fós ann tar éis bás Dolly, tríd an 19ú hAois, suas go dtí an Athbheochan sa 20ú haois

To my dismay I can not say that i know much, if indeed anything about Kernewek. As a regular visitor to Cornwall the place where Cornish is most visible to me is in the place names on the Road signs.

Is mór an t-údar díomá dom nach féidir liom a rá go bhfuil mórán eolas agam fé Kernewek. Mar chuairteoir rialta ar Chorn na Breataine, is iad na logainmneacha ar na comharthaí Bóthair na háiteanna ar a bhfuil an Choirnis is infheicthe

Some common placename elements contain the following:

Cam/Kam = Curved or Crooked (Similar to 'Cam' in irish)- E.g. Camelford, Camborne

Eglos = Church (Similar to 'Eaglas' in Irish)- Eg. Egloshayle, Egloskerry

Hayle = Estuary - Eg. Egloshayle, hayle

Lan = Enclosure belonging to a church ? - Eg, Lanivet, Lanhydrock

Pen = Headland (Similar to our 'Ceann' or 'Cinn') - E.g. Pendennis, Penzance

Pol = Pool (not unlike our own 'Poll')- E.g. Polzeath, Polperro

Tre = Farmstead or small settlement - Eg. Trevena, Trebarwith

Kernewek is a P-Celtic language & Irish is a Q-Celtic language, so it would not be as easy, for an Irish person, to read Cornish & get a grasp of what is being said, however there do seem to be some similarities

Is teanga P-Cheilteach í Kernewek & is teanga Q-Cheilteach í an Ghaelainn, mar sin ní bheadh sé furasta, do dhuine Éireannach, Coirnis a thuiscint,ach is cosúil go bhfuil cosúlachtaí áirithe ann

Examples
Treth =Beach (Trá)
Du = Black (Dubh)
Rudh = Red (Rua?)
Glas = Blue (as opposed to Green in Irish)
Gwynnrudh - Pink ( white&red, just like we say Bándearg)
Nadelik = Christmas (Nollag)
Bugh= cow (Bó)
Tarow = Bull (Tairbh)
Konin = Rabbit (Coinín)
Gavar = Goat (Gabhar)

The great news is that the revival of Cornish/Kernewek seems to be successfully gathering pace. In 2010 UNESCO reclassified the Cornish language as being in a 'process of revitalisation' as opposed to being an extinct language.

A few years back Kellys Ice Cream brand also made waves by releasing a telly ad using Cornish. Lined here:
i also found this useful online Cornish/English dictionary : https://www.akademikernewek.org.uk/corpus/?locale=en

Anyway, as i've said i'm in no way knowledgeable enough on the subject but there are a few sites such as @speakcornish20 @golearncornish @kernowlingo that discuss the Cornish language (& will actually know what they are talking about)