Sextant Poem by David McLansky

Who can plot the human heart,
An organ of ten thousand parts?
In what precision does there lay
To set its course from day to day?
By what sextant, by what globe
Can its locale, exact, be probed;
By what sun, on what horizon
Must we fix our eyes upon?
Who can call with certitude
Its position as to latitude;
Who can know its longitude
When our clocks remain so crude?
For a heart is only known
By an organ like its own;
Which moves without a gyroscope
And flounders on the Cape of Hope.