Resumen de 50, 100 & 150 years ago.
Excerpts are provided from issues of "Scientific American" magazine dated April 1969, 1919, and 1869 on topics including transuranium elements, airship travel and ice making.
Excerpts are provided from issues of "Scientific American" magazine dated April 1969, 1919, and 1869 on topics including transuranium elements, airship travel and ice making.
