I found some images of some “Skye terriers” from the later part of the nineteenth century.
Here is J. Gordon Murray’s Otter– named after its main quarry. It appears in Hugh Dalziel’s British Dogs, which came out in the late 1870’s.
This dog looks very little like the Skye terrier we know today! This animal could pass for a Scottish terrier with a strange tail or a very unusual Cairn terrier. It appears to wire-coated.
Another Skye terrier from the 1870’s was Flora. This particular image comes from 1872. She was owned by a Mr. Shaw, and she was described as a good example of a working Skye terrier in Robert Leighton’s The New Book of the Dog (1907).
This dog may be a soft-coated working Skye, and she had drop ears.
Such dogs were very different from the pet class and show-type dogs that were more common in the institutionalized fancy.
See related post:
Jesse’s “Anecdotes of Dogs” (1858) has a chapter on “Otter Terriers”. The example in the book rather resembles those pictured here.