http://tractors.wikia.com/wiki/Barth

Barth G.B were a manufacturer of the specialist machinery for land drainage, from the 1960's till 1984, based in Mablethorpe, Boston in Lincolnshire England.
Barth trenchers started out in the early 1960's to produce both wheeled & tracked trenching machines for the U.K. land drainage industry, which grew to flourish in the late 1970's & early 1980's allowing Barth G.B. to develop larger 6-cylinder Ford tractor based machines & ultimately the V8 Deutz engined K200.

Barth G.B. ceased trading in 1984 when the U.K. government extinguished the agricultural 50% drainage grant on 31st August of that year.

I do not think Robert Barth had anything to do with any companies England.

I thought he knew Margeret Thatcher.

Kenny, You got the Margeret right. but I think it was Hemingway not Thatcher.

Kevin, I thought that was Ernest.

I think that was Margeret's dad.