Angus Diarmid Ian Campbell-Gray, 22nd Lord Gray, the holder of one of the oldest baronies in Scotland, led an unconventional life for a peer of the realm.

He was at different times a hotelier, petrol pump attendant, wireless operator, and dishwasher salesman. But perhaps his most widely recognised contribution was in his time in advertising when he designed the label on the world-famous HP sauce bottle.

Lord Gray was a nobleman who could have been chief of the ancient house of Gray, but would have had to surrender his paternal surname of Campbell in order to do so.

Thus he created something of a heraldic conundrum half a century ago by successfully matriculating a coat-of-arms with a Campbell reference surmounting his Gray shield. This device was a gold label, normally of three points and indicating heirship of an eldest son to arms. Gray's label depicts two points, unique in Scotland.

Each point, however, contained the black-and-gold Campbell gyronny device, indicating his love for his Campbell descent.

''He was a very keen Campbell,'' said Alastair Campbell of Airds, Unicorn Pursuivant, his neighbour and friend. In 1971, wishing to leave London to return to Scotland, Gray purchased the small Argyll estate of Airds Bay, near Taynuilt. ''When he bought it, he was thrilled to find that his new home had been built by a Campbell ancestor,'' said Campbell of Airds.

Gray had also been in long-term discussion with the Lord Lyon regarding his numeral. As 22nd Lord Gray, he claimed ancestry to 1445 as one of the earliest peers in Scotland. There was, however, evidence to indicate that he was perhaps more than 22nd. Numeral apart, no-one doubted an ancestry that ran back to Sir Andrew Gray who in 1314 had been granted lands in Roxburghshire by King Robert Bruce. The title is one which may pass through the female line and has been held by the heads of various families, including an Earl of Moray.

Lord Gray's father, Major the Hon Lindsay Campbell-Gray, Master of Gray, MC, died in 1945, and the next year he succeeded his grandmother, Ethel Evelyn Gray-Campbell, Lady Gray, in her own right the 21st holder of the title.

A London advertising practitioner and latterly the hospitable proprietor of the Taynuilt Hotel, Argyll, he was for many years the owner of the local garage, turning out to attend the petrol pumps himself.

Educated at Eton, the youthful Gray showed natural artistic talent, and he joined the London advertising agency of Mather & Crowther, working on design, layout, and copywriting. He designed the label on HP Sauce bottles, and came up with the jingle for Fyffes: ''Let's all go down The Strand and have a banana.''

His health, however, had always been somewhat precarious and when advised by doctors in 1956 that the London smog was affecting his lungs, and that he would benefit from cold clean air, he departed for Canada. He gained a job with Bell Telephone, driving trucks and operating wirelesses in Labrador, working on the construction of the DEW-line, Canada's Distant Early Warning system of defence against Soviet attack across the North Pole.

In Canada he met Meg Alexander from Lismore in

Co Waterford, and they married on his arrival back in London in 1959. Angus returned to his love of design, this time for the packaging and marketing of dishwashers and similar ''white goods''.

A hereditary peer in the House of Lords, Gray - whose affable demeanour concealed an extremely astute brain - contributed to debates on licensing and Scottish affairs, and three decades ago urged more liberal lines for Scotland's licensing laws.

During the third reading of the Callaghan government's Scotland Bill in 1978, he successfully forced an amendment obliging the proposed Parliament of Scotland to report its proceedings.

When Tony Blair's Lords reforms were being pushed through in 1999, it was Gray who argued that the House of Lords Bill breached the article of the Act of Union of 1707 allowing 16 representative peers the right to sit in the Lords. His persuasive intervention nearly won, and it was only lost following a last-minute decision against him by the powerful committee for privileges.

He was predeceased by his first wife, Patricia nee Alexander, in 1987. He married secondly, in 1994, Cecilia (nee Dimsdale), widow of Paul Williams.

He is survived by her and his children of his first marriage, son Andrew who succeeds him as 23rd Lord Gray, daughters Lucinda, Iona, and Isobell; and grandson Alexander, now the Master of Gray.

Angus Diarmid Ian Campbell-Gray, 22nd Lord Gray; born July 3, 1931, died April 29, 2003.