NavList:

   

Reply

Michael Daly wrote:
>> That applies only to Mike's special interpretation of the instrument, and to
>> the Royal Society engraving. To an open mind things are different, with our
>> new understanding of how Newton's note can be read..
>
> I have an open mind, however, I'm not gullible. I'll accept anything
> that can be reasonably proved.  I've seen no such proof.
>
> You are continually referring to some mythical Newtonian instrument that
> you never describe and is completely undocumented.  Provide a reliable
> source or drop the fantasy.
>
> Mike
Mike,
I freely admit my knowledge of this subject as limited to what I have
read in CDR Bauer's book, "The Sextant Handbook" of which I hope the
good CDR does not mind me quoting rather liberally.  As to whether or
not he is a reliable source I leave that to your opinion. IMHO he seems
to treat this subject fairly and objectively on pp 25-35.  So here goes.

Page 25, CDR Bauer says:
"In 1699 Sir Isaac Newton (1642-1727) conceived the principle of
measuring angles by double reflection and made an instrument that would
do so."

Does this mean that Newton actually produced a working prototype or just
a drawing?  I suggest that it doesn't matter, the drawing is as good as
the prototype.  However, I DO believe Newton made a working prototype of
the double reflecting instrument see below.

Page 26, CDR Bauer says:
"On 9 August 1699, the celebrated Newton, the Einstein of his age,
personally appeared before the Royal Society to reveal a new principle
of optics to this group whose purpose was to receive, evaluate and
disseminate scientific knowledge. He read and submitted a paper on an
instrument made on the principle.  From the Journal book of the Royal
Society (minutes of the meeting), set down in a bold and flowing script:

      Mr Newton shewed a new instrument contrived by him for observing
      the moon and starrs, the longitude at Sea, being the old instrument
      mended of some faults with which notwithstanding Mr. Hally (sic)
      had found the longitude better than the Seaman by other methods.

The minutes were referring to Edmund Halley (1656-1742), later the
secretary of the Royal Society, who applied Newtons concepts to predict
the comet that bears his name.  In 1699 Halley had recently returned
from a voyage to Brazil, during which he evaluated an instrument
designed by Dr. Robert Hooke, a rival of Newton.  Hooke's instrument
used a mirror, but did not incorporate the double reflecting principle.
  It did not work very well.

This Royal Society Journal book entry constituted a clear record of what
in current patent office terminology would be called disclosure of a new
invention.  That someone was listening attentively is demonstrated by
the insertion of a comment in the minutes of the next meeting -- 25
October 1699 -- by Dr. Hooke that:

     ...the instrument mentioned last meeting was of his [Hooke's]
        invention before the year 1665 and that the use and fabric of
        it was declared in the History of the Royal Society.

He disputed the originality of Newton's concept or model or both.  We
cannot tell which."

So now we have Sir Isaac Newton and Dr. Hooke (rivals) saying they each
invented the double reflecting principle and an instrument to measure
such.  Newton in 1699 and Hooke sometime before 1665.  Again according
to Bauer, John Hadley in 1731 presented yet another paper to the Royal
Society on the double reflecting principle and TWO prototypes.  It was
one of these prototypes that went into commercial production shortly
thereafter.  Further, at the same time as Hadley, Thomas Godfrey (an
American and close associate of Ben Franklin) also laid claim to
developing the double reflecting instrument.  Ultimately, the Royal
Society settled the Godfrey/Hadley dispute by saying it was
"simultaneous and independent invention".  Both of these instruments use
the double reflecting principle but look sufficiently different.  And
actually these instruments were octants not sextants.  So there you have
it, abbreviated sextant history according to CDR Bauer.  There is much
more in the book and I can highly recommend it.

--Scott

--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@navlist.net
To , send email to NavList-@navlist.net
-~----------~----~----~----~------~----~------~--~---

   

Reply