Point of Interest Dossier: The River MothCopy Anchor Link

"A towel, it says, is about the most massively useful thing an interstellar hitchhiker can have. Partly it has great practical value... use it to sail a mini-raft down the slow heavy river Moth..."

— The Hitchhiker's Guide to the Galaxy, Chapter 3

The River Moth is a legendary, meandering waterway celebrated in The Hitchhiker's Guide to the Galaxy for its languid current, high-density mineral waters, and scenic riverbanks that invite low-cost aquatic hitchhiking.

Hydrological Characteristics: "Slow and Heavy"Copy Anchor Link

Why does the Guide specifically describe the River Moth as both slow and heavy?

• High Specific Gravity: The waters of the Moth are naturally rich in suspended colloidal silicates and harmless heavy-water isotopes, giving the river a remarkably high specific gravity. Even a hastily lashed-together mini-raft of driftwood floats high and dry on its glassy surface without sinking.
• Languid Current: Flowing across a virtually flat alluvial plain for thousands of miles, the current moves at a stately pace that allows travelers to nap, read the Guide, or dangle their toes over the side without fear of unexpected rapids.

The Mini-Raft & Towel Rigging ProtocolCopy Anchor Link

Because commercial river-ferry operators along the Moth charge exorbitant fares in Altairian Dollars, seasoned hitchhikers rely on the time-honored Towel-Sail Method:

1. The Mast: Wedge two sturdy branches upright at the bow of a mini-raft.
2. The Sail: Tie the corners of a largish Massively Useful Towel (such as a bath towel from Marks and Spencer) across the spars to catch the warm afternoon river breezes.
3. The Drying Stage: Once the voyage concludes at the river delta, the wind-dried towel is immediately ready to be folded back into the hitchhiker's satchel.