Washington DC: GPO, 1951. Pamphlet. Translated from English-language original(s): 74p., profuse line-drawn illustrations for the adult tinkerer, softbound, a pamphlet in 9x6 inch plain printed green wraps, mild edgewear, mild toning to text-block, a good to very good copy.
Perhaps influenced by diplomatic recognition of the Franco regime; the other copies listed on the net seem all to have landed in Spain, and are issuing from Spain, not from any other Spanish-speaking country. Date of presswork is, FYI, to be seen in minuscule smallpoint on the very last page.