Yes that s the one I think Hentschel of Fleet St were just the printers who pioneered the 3 colour process in the UK But exactly which of the many 3 colour techniques it was I m not sure I suppose it could have been an early form of the modern photographic process with filters When I said above From memory only her first one or two books were printed using wood blocks I might have been thinking of Kate Greenaway A quick look at Bamber Gascoine does not clear up any of this