Quotation from: The Notebooks of Leonardo Da Vinci

Written by: Leonardo da Vinci

[Footnote 12: The Abbey of Chiaravalle, a few miles from Milan, has
a central tower on the intersection of the cross in the style of
that of the Certosa of Pavia, but the style is mediaeval (A. D.
1330). Leonardo seems here to mean, that in a building, in which the
circular form is strongly conspicuous, the campanile must either be
separated, or rise from the centre of the building and therefore
take the form of a lantern.]