What does Grant v Australian Knitting Mills establish?

That even know in a shop the goods are on the counter in front of them, they are still a sale of description. a thing is sold by description, though it is specific, so long as it is sold not merely as the specific thing, but as a thing corresponding to a description, e.g. woollen undergarments, a hot-water bottle, a second-hand reaping machine, to select a few obvious illustrations.