1887, September (pub): Myself and Myself
On the Isle of Skye, Scotland, a tale is told of a shepard's wife who had an unexpected visitor while her husband was out fishing on the nearby lake. As the shepard's wife was busy making dinner, a very handsome young man walked into the house unannounced and sat upon a chair, stikeing up a conversation with the wife. A wary woman under the circumstances, when the strange young man asked for her name she was sure to answer 'Mi fhein 's mi fhein'... "Myself and Myself." In observing the young man, the wife had noticed through his loose jacket that his chest was covered with long, grey hair... which told her that the odd guest was in reality a kelpie, or water-horse. She made as if to give her visitor some of the porridge she had brewed, but smacked him on the head with the pot instead. Up the strange young man jumped and out he ran, holding his head and yelling loud enough that his father rose from the lake to see what the noise was all about. The young water-horse was asked who hurt him, to which he immediately answered "Mi fhein 's mi fhein!"... "myself and myself." The water horse's father replied "if any other kelpie or human being had hurt you I would have avenged you; but since you hurt yourself, you may bear the pain!"
The above tale was collected orally from Scotland by Alexander MacBain, and published in the Celtic Magazine in 1887. MacBain was very much under the impression that the original inspiration for the tale was the Greek story of how Ulysses blinded a Cyclops, and told it his name was "No-Man"... so when asked who hurt it, the Cyclops replied "no man," and thereby received no help.
More notable is the idea that the young man was identified as a water-horse due to long grey hair on his chest... mainly because this tale alone is the only time I've ever run into that as criteria for recognizing a transformed water-horse! This tale is also clearly related to a similar tale that was published in 1900: use the link below to see it.