Didn't Get Information on Hobson Drive for Dead Axiel Trucks

this post is about a traction device fitted to a leyland 6x2 to in the 60s enabling it to behave like a 6x4 when a roller was employed to press onto the tyres of both wheels making the driving wheel drive the trailing axel wheel i think it was called a Hobson Drive. any drawings or pictures of same would welcome i am sure i seen the article in the Commercial Motor Magazine but it is years ago Thank you

Bertie Hemphill