ANCIENT SAILING & NAVIGATION

[John C. Mannone]

Ancient sailors were really challenged to navigate over open water. Any good source of information on ancient celestial navigation you can recommend?

I found some interesting star charts used by Hawaiians and Polynesians to navigate the islands. My main nterest is before 100 AD.

Reading "The Odyssey" (Homer ~800-900 BC) stimulated my interest in this area.

Thanks.
Starry nights and fair winds,
John

[Todd Bradshaw]

You might enjoy the book "Latitude Hooks and Azimuth Rings" by Dennis Fisher (International Marine - WoodenBoat may sell it). It has a bunch of plans for building old navigation gizmos, some quite ancient and information on how they are used. It's kind of a fun book.

[Mike Field]

.
Good suggestion Todd.

Publisher International Marine, Camden, Maine, 1995.
ISBN (A4 paperback) 0-07-021120-5

Contents --

Tools and materials
Latitude hook
Kamal
Astrolabe
Quadrant
Astronomical ring
Sundial
Nocturnal
Cross-staff
Backstaff
Dry-card compass
Traverse board
Hand lead
Heaving line
Chip log
Weatherglass
Pelorus
Sun compass
Octant

What they are and do, and drawings and instructions for making them.
.

[John Gearing]

There are a couple of good books out on the near-lost arts of Polynesian navigation. IIRC one is "The Last Navigators" and one of them was written by Dave Thomas before he got his gig with "This Old House" aka This Old Dream House that you can't afford. The Polynesians, as I recall, picked up subtle things like differences in wave patterns, cloud formations, etc to tell what was over the horizon. As for 100AD in and around Europe, I don't recall there being much of a solid record of anyone venturing very far offshore.

[Bill Perkins]

A book of mine mentions The Magic Calabash , a hollow gourd or gourd like instrument for taking altitudes that the Polynesians had since way back . Holes were punched symmetrically around the base , probably by partially submerging the gourd .In use , water was placed Inside the gourd and when its' level just touched all the holes the instrument was referenced to the horizontal plane .Two more small holes were added for sighting through such that Polarus was visible when standing on your home Island , fixing its latitude .Returning home they'd run due North or South to the correct Latitude , then East or West to their home , getting close enough to use the info John mentioned. According to the same book Europeans were navigating in a similar way at the period you mention , also I think , the desert navagators . What's the Southern most latitude from which Polarus is visible ? I'd be interested to know if the pattern of human trade and migration was different below the sight line of that critical Nav star . Slower and more uncertian I would think .

What came later was using a calibrated compass card and mathematics to cut the corner or sail the hypotenuse of the former North-South East-West voyages , traversing the Meridians in so called Traverse Sailings .

[ 02-03-2003, 02:15 PM: Message edited by: Bill Perkins ]

[jstraker]

Hello, there. A couple of good books by David Lewis, a New Zealander (who recently passed on) who dedicated around a decade of his life or so, it seems, to figuring out how people got around the Pacific. One is "The Voyaging Stars", and the other, "We, the Navigators" which is sort of a more technical version of the first. Very good reads, and pretty amazing stuff. These guys were SAILORS!

[Bruce Hooke]

Polarus is on the horizon at the equator and below it anywhere in the Southern Hemisphere...

[Ian G Wright]

Originally posted by Mike Field:
.

Dry-card compass**
Traverse board** (tables)
Hand lead**
Heaving line**
Chip log**
Pelorus**
Sun compass**(shadow stick)
.I still carry the ones above, doesn't everybody?

IanW.

[J. Dillon]

http://www.imagestation.com/picture/sraid49/p063c7de2af75c88cbf7698e563417bc3/fcaff5a3.jpg

This image scanned from "We the Navigators" shows the helmsman steering with the tiller arranged facing aft. Pacific islanders used whatever available to steer their craft, in this case a natural "crook" attached to the rudder.

Another excellent book if you can get it, is the "Raft book" by Harold Gatty. First published in 1943. It was designed as a survival book for airmen and seamen in life boats during WW2. I covet my copy of this book.

JD

[John C. Mannone]

I appreciate the wonderful reading suggestions. They are especially good for sailing after the 1st millennium AD. I remember reading about the Polynesian helmsman, too. You can imagine the increased difficulty when very few or no instruments existed.

Here is a little background that might stimulate discussion.

Around the 3rd century BC, Aratus, a Greek poet, had put to poetry (meter, no rhyme) the rising and setting of the 43 (then known) constellations to help the farmers, but particularly, the sailors. Aratus was nearly as popular as Homer in the 1st century AD.

However, the much earlier 8th century BC work of Homer cites much fewer celestial navigation aids: Sirius, Arcturus (in Bootes), Ursa Major (The Great Bear or Wain, the Wagon), Pleiades, and Orion for the most part (incidentally, many of these are also mentioned in the Holy Scriptures- Old Testament). The additional difficulty was that there was no North Star; due to Earth’s precession, the spin axis pointed into empty space during those years. Celestial navigation in the Northern Hemisphere is easier (still assuming no instruments) today with Polaris giving us a North fix.

In “The Odyssey”, Book V, Ulysses is trying to get back home to Greece some 400 nm miles away and his sailing directions from Ogygia (Malta) are given in celestial terms. (Due to mitigating circumstances, he ends up in Phaecia (Corfu) somewhat NW of his destination, Ithaca). Listen to the poetry:

"Moreover, she made the wind fair and warm for him, and gladly did Ulysses spread his sail before it, while he sat and guided the raft skillfully by means of the rudder. He never closed his eyes, but kept them fixed on the Pleiads, on late-setting Bootes, and on the Bear- which men also call the wain, and which turns round and round where it is, facing Orion, and alone never dipping into the stream of Oceanus- for Calypso had told him to keep this to his left. Days seven and ten did he sail over the sea, and on the eighteenth the dim outlines of the mountains on the nearest part of the Phaeacian coast appeared, rising like a shield on the horizon."

It seems he secured the rudder/tiller and drifted with a seasonal northeast current (thermohaline, about 2 kts), which took him in the approximately correct direction during the day. On clear nights, he made the necessary course corrections by the stars. Of course, this is my conjecture.

When I tried to follow these sailing instructions with planetarium software (Starry Night Backyard v3), I quickly realized Ulysses had a daunting task.

As far as celestial navigation in the Southern Hemisphere, there is no pole star there even now. There are some faint stars near the South Pole, but there are close to the limit of visual detection. However, the whole of the Milky Way with many bright stars rotate around the pole. I imagine a large swath of stars could be used in much the same way Ulysses used Ursa Major.

Starry Sails,
John

[Mike Field]

.
Interesting stuff, John. I don't know about old-time navigation south of the equator, but in more modern times (but sans modern equipment,) I think any navigator would be using for direction the Southern Cross (Crucis) with or without its Pointers (alpha- and beta-Centauri,) rather than the Milky Way..

[John C. Mannone]

Hello Mike,

We are both right. I fired-up my planetarium software, Starry Night Backyard, and took a quick look at the Southern Hemisphere. The Southern Cross and the even brighter nearby Alpha and Beta Centauri stars, are in the Milky Way.

Other stars to complement these were probably used for celestial navigation. Canopus (Alpha Carinae) is in the former constellation of Argo, a great sailing ship captained by Jason. Canopus is second brightest star in the heavens (Sirius in the Northern Hemisphere is the brightest). Achernar (Alpha Eridani) is also brighter than the Crux stars. These stars are distributed over half of a “circle” roughly the same distance around the pole. For example, in the present day, when the Southern Cross is crossing the lower meridian, Archernar is near the upper meridian, while Canopus is approximately to the left. They are circumpolar, but depending on the millennium, some will be closer or further (and therefore go below the horizon). Archernar comes in much closer to the pole than the other stars 4000 years ago; and this squashes the “circle” mentioned above.

It seems almost assuredly, that these stars in concert helped ancient and more recent mariners navigate the Southern Hemisphere.

Thanks for your contribution,
John

[brian.cunningham]

Google search ...

<a href="http://www.pbs.org/wgbh/nova/longitude/secrets.html" target="_blank">NOVA - Secrets of Ancient Navigation
</a>
Now to Miletos he steered his course
That was the teaching of old Thales
Who in bygone days gauged the stars
Of the Little Bear by which the Phoenicians
Steered across the seas
<a href="http://www.celestialnavigation.net/wayfinding.html" target="_blank">Wayfinding
</a>
Traditional Navigation in the Western Pacific - A Search for Pattern (http://www.museum.upenn.edu/navigation/Intro.html)

[ 02-06-2003, 12:05 AM: Message edited by: brian.cunningham ]

[John C. Mannone]

Thanks Brian. These are good sites.

John