How I Then Tried to Diffuse the Theory of Three Dimensions by Other Means, and of the Result
My failure with my grandson did not encourage me to communicate my secret to others of my household; yet neither was I led by it to despair of success. Only I saw that I must not wholly rely on the catchphrase, “Upward, not Northward,” but must rather endeavour to seek a demonstration by setting before the public a clear view of the whole subject; and for this purpose it seemed necessary to resort to writing.