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nydus/On Growth and FormPublic
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CHAPTER XI THE LOGARITHMIC SPIRAL

to Turbo duplicatus, on page 519, it is perhaps worth while to illustrate the logarithmic statement of the same facts: that is to say, the elementary corollary to the fact that the successive radii are in geometric progression, that their logarithms differ from one another by a constant amount. {521}

Turbo duplicatus.
Relative widths of successive whorlsLogarithms of successive whorlsDifference of successive logarithms
1312ôñ11727〇〔
1122ôñ04922〇ôñ06805
941ôñ97313〇ôñ07609
801ôñ90309〇ôñ07004
671ôñ82607〇ôñ07702
571ôñ75587〇ôñ07020
481ôñ68124〇ôñ07463
411ôñ161278ôñ06846
Mean difference ôñ07207

And ôñ07207 is the logarithm of 1ôñ1805.

A grayscale, overhead view of a single nautilus shell showing its internal spiral structure.

The logarithmic spiral is not only very beautifully manifested in the

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