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LONGCAMP.COM'S
NOVA ALBION ANNEX
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Francis Drake at
Campbell Cove
by Bob Graham
A DEMONSTRATION AT CAMPBELL
COVE: On
October 6, 1999, Brian Kelleher (right) issued a press
release announcing a meeting at noon on October 30 at
Campbell Cove. Following an article and announcement by Carl
Nolte, San Francisco Chronicle Staff Writer, on the 29th,
about 45 people attended.
The intent of this meeting was to provide a demonstration
by this writer (left) of Drake's ability to read the
altitude of the sun with an astrolabe or quadrant, and to
show what his determination of latitude would have been. It
was a bright clear day with a light breeze from the
northwest. Typically, for this place, the actual horizon was
obscured by mist. The astrolabe requires no visible horizon,
so this would be no problem.
On this day, due to the equation of time, the sun was
approximately 16 minutes before the clock. Campbell Cove
(123 W) is also 3 degrees west of the 120th meridian Pacific
Standard Time 12:00, making it 12 minutes late by the clock.
Therefore, the actual meridian transit of the sun (see watch
in photo) occurred at about 12:56 PDT (11:56 PST).
About the watch and how easy it is today to carry the
correct time about.
The computed angle that the sun was expected to rise to
was N38° 01' 37". The highest angle (see spot of
sunlight passing through the foresight and projected onto
the back sight in the photo) that could be read on the
scales of both the astrolabe and quadrant was 38 degrees.
Applying standard modern reductions for the day and
longitude to the 38 degrees of the sun's altitude resulted
in a determination of latitude of N38° 19'. The actual
latitude by GPS was N38° 18' 19".
To
show the determination that Drake would have made, the solar
declinations of William Bourne (for October 20 old calendar
and adjusted to bring them up to 1999) were then used.
Because Drake could not, the declinations were not corrected
for longitude. This reduction resulted in a determination of
N38° 24'. This is about +7 miles north of the actual
position. It is, however, a very good determination due to
the season of the year.
The error near the solstice, when Drake's visit occurred,
would have been larger. This is reproduced in the on the
right, which shows the altitude of the sun as Drake would
have observed it on June 30 (old calendar). The sun is, of
course, much higher at its meridian--much higher than it
would have been possible to measure using the cross staff.
During the 37 days of his stay, a noon sighting of the sun
at Campbell Cove (N38° 19') would have yielded a
determination ranging from N38° 24' to N38° 42'.
The average determination would then have been N38°
30', exactly as recorded in The World
Encompassed.
The publication of The Famous Voyage (1596)
predates the appearance of The World Encompassed
(1628). However, the latter includes far more detail than
the earlier publication. This added detail cannot be
invention, or filler, as it includes details
of the peoples encountered and places visited which can be
verified. The two accounts must have come from the same
original source.
So, was the detailed latitude determination for New Albion
(only) in The World Encompassed deliberately
distorted for some reason? Does it purposely misstate the
latitude of Drake's landing place at Nova Albion to throw
off the Spaniards (conspiracy theory?), or does it record
"N38deg.30.min" because that was indeed Drake's
determination?
14th
Century English philosopher William of Ockham said,
"entities must not be unnecessarily multiplied." Well, he
wrote it in Latin, actually--entia non sunt multiplicanda
praeter necessitatem. This has become known as
"Ockham's Razor." What does it mean? Click the
picture!
See the article DETERMINATION OF LATITUDE
BY FRANCIS DRAKE ON THE COAST OF CALIFORNIA IN
1579
What does the Drake Navigators Guild (the DNG)
say about the latitude of Drake's landing site? This page
includes my analysis of the Guild's accepted latitude.
Timothy Burke has an interesting page The Astrolabe
on the De Soto Expedition.
interest, comments, or
questions.
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