Aboard the Anima  ·  Below deck, aft

The Chart Room

Every ship keeps one: a quiet room below the bridge, where the course is checked against the numbers before anyone trusts the wind.

Tom followed, ducking through the low hatchway into the navigation room. It was a small space, warm with the smell of lamp oil, old paper and strong tea, the walls lined with rolled charts secured by leather straps. A single brass lamp hung from a hook in the ceiling, swaying slightly with the motion of the hull.

From Anima  ·  Chapter 1, The Crowd
The doubling glass

How long until it doubles?

Set the yearly rate. The glass turns.

Rule of 72, checked against the exact figure. Assumes the return is reinvested every year.

The chart room's instruments

Reckoning time

The long voyage is not crossed in a day. These measure what patience does over years. They are kept at CalcSnap, by the same hand.

Compound Interest Small, steady winds. See what they do to a sum left alone for thirty years. Open instrument → Rule of 72 The navigator's shortcut: how many years before what you hold has doubled. Open instrument →
From the log
Compound Interest: The Numbers Behind "Start Early" What waiting five or ten years really costs, in plain numbers.
Elsewhere aboard

The ship's other instruments are kept in their own rooms now.

Value: the Binnacle Safety: the Helm Dividends: the Hold Loans: the Harbour Office Writing: the Logbook Riddles: the Night Watch
Anima — The Most Important Investment, 2nd edition
The ship in the book

Anima
The Most Important Investment

The instruments can do the arithmetic. They cannot tell you what is worth holding. That question is the voyage, and the book is where it is asked.

Paperback Kindle

These are instruments, not advice. Numbers chart a course; they do not sail it for you. All calculators give estimates for education only. Check important decisions with a qualified professional.