The 'Humper' - a new handling machine for builders. Revised version of article appearing in: The National Builder, 1963, vol. 44, May, pp. 471-2, 475, also published in The contract journal, 1963, vol. 172, May 9th, pp. 179-80.
Vallings, Harold Gordon.
[Garston, 
1963]
Reproduced from typewriting.