Akshully, Tonald, me ould fruit, I had been researching articles on The Craigallian Fire..... which my grandfather frequented before - and after - his Spanish Civil War episode.... which turned up some old pieces 'online' in The Herald. One was an journo's appreciation of 'An Leabhar Liath' in the sidebar.
Serendipity. That's all.
I don't need to stumble upon arcane erotica. I know exactly where to find the Real McCoy.
On a slightly more esoteric note, the translation gives liath = light blue. This is interesting because liath is usually translated as grey. But glas is also usually translated as grey. I have for some time thought that these describe different shades of grey.
Doing a little digging, Faclair Beag gives liath = 1 grey 2 grizzled while Dwelly gives liath = Grey, grey-coloured. 2 Greyheaded, grey-haired. 3 Mouldy. 4** Lilac. 5** Pale. 6 (AH) In dyeing this word describes a very light blue colour. Liath is dubh, light blue and black; falt liath, grey hair, aran liath, mouldy bread.
Faclair Beag interestingly also gives liath-uaine = grey-green and liath-ghlas = 1 light grey 2 hoary.
Faclair Beag gives glas = 1 grey-green 2 pale, wan, sallow 3 green, unripe while Dwelly gives glas = Grey, pale, wan, ashy, sallow. 2 Poor. 3(DC) Green, as grass, unripe corn, &c
From that I think it safe to say that while both liath and glas each cover a range of shades they are quite distinct. However, on translating blue to gaelic both dictionaries give gorm which can mean either blue or green! This really isn't easy.
The other gaelic colours which had me puzzled were ruadh and dearg, both of which are normally translated as red.
Faclair Beag gives ruadh = (browny) red, rust-coloured, ginger, russet (used for natural fibres e.g. hair, wool...) and Dwelly gives ruadh = Reddish, of a reddish colour, ruddy. 2 Red in general. 3 Red-haired. 4 Dried, scorched. 5** Brown. An tuil ruadh, or an dìle ruadh, the general deluge; sgillinn ruadh, a penny; Seumas ruadh, red-haired James.
Faclair Beag simply gives dearg = red colour while Dwelly is more fulsome, giving dearg = Red, ruddy. 2 Flaming. 3 Red-hot. 4 Real, very, intense, inveterate. 5 Violent. 6 Downright mad. 7* Most abandoned or notorious. 8 Complete. 9** Bitter. 10** Severe. 11** Turned or ploughed. 12†† Impetuous. 13 Gules, in heraldry, represented by perpendicular lines, see illust. Dearg amadan, a complete fool; dearg mhèirleach, a notorious thief; dearg strìopach, a most abandoned strumpet, prostitute; dearg mar fhuil, red as blood; air an dearg chuthach, stark mad; talamh dearg, turned or ploughed land; feòil dhearg, red or raw flesh. [Dearg is often prefixed to a noun when it is required to express an extraordinary degree of guilt, &c., as, tha an dearg-chiontach saor, the glaringly guilty is free; tha an dearg chuthach air, he is mad with rage.
My tentative conclusion from this is that dearg is a brighter or more intense red than ruadh.