LECTURE II
THE LENGTH OF OUR VOYAGE AND THE START THROUGH THE AIR
We have talked of the primary great difficulty of getting away from the Earth at all. But it is not quite fatal, for balloons and aeroplanes do allow us to leave the solid Earth in some measure. We have just read in the newspapers that an aeroplane has ascended to a height of nearly four miles, and the question arises whether this is as far away as we wish to go. If we have any idea of visiting the Moon, then it is not nearly far enough, for the Moon is not four, but 240,000 miles away; an aeroplane must beat the present record by a considerable margin if it is to take us to the Moon. It is not altogether easy to realize what such a distance means, even when we remember that it is about ten times round the Earth. A little time ago there was a story in Pearson's Magazine of an American who used a huge searchlight apparatus to throw an advertisement on to the Moon, "USE MOON SOAP." The picture does not suggest any great difficulty in this achievement until we remember that owing to the Moon being 240,000 miles away, each of the letters would be hundreds of miles high; and then we begin to wonder whether even the most powerful searchlight
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