The Underground Movie (1972)

Everyone has wondered what it would be like to dig right through to the other side of the Earth. This animated film takes the wonder a step further. Here the probe is accomplished with a machine as ingenious as any that have reached the moon. Dubbed 'Old Chucknose' and equipped with amazing gadgetry, it bores through every layer of the Earth's crust and centre. Perhaps it's not a blueprint of things to come, but it's plausible enough as observed in this cartoon.