Slocum's Navigation

[sneuman]

Originally Posted by MichaelC

Slocum didn't have jet contrails.
When I was preparing for my first ocean crossing, I took a class in celestial navigation. The instructor was incoherent. I was talking to an old fisherman at Seattle's Fisherman Terminal [this was in the 70s], and he scooped the snoose out of his mouth, and told me how to find Honolulu. Go out the Strait of Juan de Fuca, hang a left. When your AM radio picks up San Diego, hang a right. Follow the jet contrails. They are all going to Honolulu. I took some books and my radio and my watch and a Davis plastic sextant. He was right about the contrails, and I taught myself to navigate on the way over.

great story!

[skipmac]

Originally Posted by boatman61

I guess folks were more intuitive back then. also they were not as obsessed with pinpoint accuracy... one made as accurate a general direction as calculably possible then made adjustments as/when visble marks appeared to confirm ones position on the chart... working within errors was a way of life
Pretty much how I sail today... when GPS dies...

Well I think not just intuitive but using many more tools than most modern navigators.

First, navigators in Slocum's time kept really good DR plots, knew the tides and currents and allowed for set, leeway, etc. so good sailors in that time could keep a better DR position than the average sailor today.

They also used a lot of indirect clues for landfall like observing bird species and time and direction of flight, cloud formations, blink (reflection of light or color from ice, land or shallow water banks), sea weed, water color, etc.

Then there were a lot of practices to allow for uncertainty in navigation like heaving to or standing off at night or in poor visibility, allowing wide berth to hazards, a lot of heaving the lead, etc.

All in all, a lot more work that modern sailors who can sit back and look at the plotter.

[Andres_RG]

Sailing Alone Around the World by Joshua Slocum

Free copy of the book in PDF
http://www.riapress.com/Sailing-Alone-Around-the-World/?-session=StoreSession:5282CCF21e082230A6UyM11CDF2B


Happy new year 2011,

[goboatingnow]

He used dead reckoning for longitude and apparently only took one lunar observation during the entire circumnavigation. He used an approximate time, and Noon Sun sights for latitude.

I think the guy was just winging it and got lucky.

Ive read his book from cover to cover several times, but I dont have rose tinted glasses, , he was a classic "wing-it" merchant who got lucky ( and then didnt).

Dave