The handle does certainly look like an Ettrick style which (over here) usually has a wharncliffe or pruner blade (same curved handle). I'd imagine this started off life as a pruner blade too. Bulldog seems to have been a tagline for US and German firms I think

so that's not helping me, and as for the tang stamp, the only P&W MacLellan that Google is throwing at me is a Glaswegian construction company.
Nice looking knife, and looks like it's got plenty of years life left in it yet
