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Author Topic: Can you add to the list of sextant numbers?  (Read 312425 times)

John Ousterhout

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Re: Can you add to the list of sextant numbers?
« Reply #135 on: November 03, 2012, 10:25:18 AM »

In the discussion about the seven site, John Kada includes a nice description of the use of a sextant for hydrographic survey work.  It's worth noting that a "bubble octant" cannot measure the angles between two points - they only measure the vertical angle from a simulated horizon (indicated by the bubble held centered to create a reference horizontal plane) to a point somewhere between the horizon and vertically overhead.  It doesn't work if it's tilted.  A nautical sextant measures the angle between any two points, even while tilted on it's side.  For example, a flying boat might want to record a nice mooring spot in the middle of a lagoon.  By picking two identifiable points on land, and precisely measuring the angle formed between them from that mooring location, plus either a compass bearing or a 3rd point, the mooring spot can be readily found again by any future visitor with a similar sextant.
Apologies for thread drift - I'd be happy to move this posting if a better thread was suggested.
Cheers,
JohnO
 
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richie conroy

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Re: Can you add to the list of sextant numbers?
« Reply #136 on: November 14, 2012, 05:21:02 PM »

Hi All

I had quick look at list, But didn't see maker number 2919 so here is link to ended ebay page http://www.ebay.com/itm/Brandis-U-S-Navy-Survey-1946-Sextant-Mahogany-Box-/160623039450

My apologies if this has already been seen

Thanks Richie
We are an echo of the past


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Martin X. Moleski, SJ

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Re: Can you add to the list of sextant numbers?
« Reply #137 on: November 14, 2012, 07:17:19 PM »

I had quick look at list, But didn't see maker number 2919 so here is link to ended ebay page http://www.ebay.com/itm/Brandis-U-S-Navy-Survey-1946-Sextant-Mahogany-Box-/160623039450

The seller was offering just a box.

It is in the table already.  By accident, this link happens to take you directly to the entry.  Because the pattern is for the maker's number to be inked and the Naval Observatory number to be die-struck, I've put the entry under N.O. 2919 with maker number 5310.  I think Andrew contacted the seller to get that number.

LTM,

           Marty
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Jimmie Tyler

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Re: Can you add to the list of sextant numbers?
« Reply #138 on: November 26, 2012, 04:28:53 PM »

 Hello all, I am a newbie to the forum, this only being my third post. I have came across a web sight that has a plethora of sextant, and octant information, and photos. http://landandseacollection.com/id2.html

 I apologize if this source of information is already within this thread. Did not see it posted anywhere. Furthermore, I have a distant relative, whom lives in town, that I am told has a extensive collection of antique sextants. I am in the midst of making arrangements to examine his sextant collection. I am very excited about it, and hope that I can produce some valuable information, and photos for the table in Ameliapedia.. 
Jim, TIGHAR #4064
 
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Martin X. Moleski, SJ

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Re: Can you add to the list of sextant numbers?
« Reply #139 on: November 26, 2012, 05:39:22 PM »

Hello all, I am a newbie to the forum, this only being my third post. I have came across a web sight that has a plethora of sextant, and octant information, and photos. http://landandseacollection.com/id2.html

 I apologize if this source of information is already within this thread. Did not see it posted anywhere. Furthermore, I have a distant relative, whom lives in town, that I am told has a extensive collection of antique sextants. I am in the midst of making arrangements to examine his sextant collection. I am very excited about it, and hope that I can produce some valuable information, and photos for the table in Ameliapedia..

Pleased to meet you, James.

The Land and Sea Collection doesn't have any Brandis sextants or boxes.  Those are the only ones, to my knowledge, that have, to date, exhibited the pairs of numbers found on the Niku Sextant. 

I'm looking forward to your report on what you find at your relative's house ...
LTM,

           Marty
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Bruce Thomas

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Re: Can you add to the list of sextant numbers?
« Reply #140 on: November 26, 2012, 06:10:09 PM »


The Land and Sea Collection doesn't have any Brandis sextants or boxes.  Those are the only ones, to my knowledge, that have, to date, exhibited the pairs of numbers found on the Niku Sextant. 


Well, actually I do see a tantalizing image of a Brandis sextant and its box on the Land and Sea Collection!  And on the arc of the sextant (or more properly, apparently it's a "quintant" rather than a "sextant") is the typical scribing of the Navy number.  The last digit is obscured by the apparatus covering over it, but the Navy number looks to be 142? -- TIGHAR's table of sextants in Ameliapedia has an entry for Navy number 1421.
LTM,

Bruce
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« Last Edit: November 26, 2012, 06:25:17 PM by Bruce Thomas »
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Gary LaPook

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Re: Can you add to the list of sextant numbers?
« Reply #141 on: November 26, 2012, 07:14:51 PM »

[

Well, actually I do see a tantalizing image of a Brandis sextant and its box on the Land and Sea Collection!  And on the arc of the sextant (or more properly, apparently it's a "quintant" rather than a "sextant") is the typical scribing of the Navy number.  The last digit is obscured by the apparatus covering over it, but the Navy number looks to be 142? -- TIGHAR's table of sextants in Ameliapedia has an entry for Navy number 1421.

Now this is funny. The Land and Sea Collection website, in describing the Brandis sextant adds:

"NOTE: A quintant has a range of arc of 144° compared to a sextant which reads to 90°. This was helpful in measuring Lunar Distances, which was a means of determining longitude without a chronometer."

A sextant reads to 120° not 90°. An octant reads to 90°.  These instruments get their names for the portion of a full circle that the arc covers. A quintant has an arc covering one-fifth of a circle; a sextant, on-sixth; and an octant one-eighth Because of the operating principle of double reflection, these instruments measure twice the length of their arcs. A quintant measures two-fifths of 360° or 144°; a sextant measures two-sixths of 360° or 120° and an octant measures two-eighths of 360° or 90°.

What makes this so funny is that the website goes on to brag about their expertise about all things navigational:
   
"OUR QUALIFICATIONS: We are one of the few still selling navigation instruments that know anything about them. For purposes of judging whether Joel's opinion counts, he was the editor of the chapter on sextants of the 1977 Edition of "Bowditch", The American Practical Navigator, NAVPUB 9; a member of the U.S. Naval Academy Navigation Symposium, 1975 -1978; the author of a book on marine sextants, Cornell Maritime Press,1975, and the founding president of Nautech Maritime Corporation which partnered with Tamaya of Japan in the introduction of their sextants and the famous NC-2 navigation computer, in the U.S. market. Joel is also a retired Master Upon Oceans, and held a U.S. Navy "D" Qualification as a Senior Skipper - Oceans. From 1995 through 2000, he served as a Varsity Offshore Sailing Team coach at the U.S. Naval Academy."

-------------------------------------

What a hoot.

gl
« Last Edit: November 26, 2012, 07:18:14 PM by Gary LaPook »
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Jimmie Tyler

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Re: Can you add to the list of sextant numbers?
« Reply #142 on: November 26, 2012, 07:22:12 PM »

I was just fixing to post the link to that Brandis, from the land and sea collection.. But I see Mr. Thomas beat me to it...
Jim, TIGHAR #4064
 
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James G. Stoveken

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Re: Can you add to the list of sextant numbers?
« Reply #143 on: November 26, 2012, 08:59:54 PM »

If you check the links Bruce provided you'll see that this sextant/quintant/whatever is Brandis serial #3331, N.O. # 1421 and is already listed in the Ameliapedia.
Jim Stoveken
 
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Martin X. Moleski, SJ

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Re: Can you add to the list of sextant numbers?
« Reply #144 on: November 26, 2012, 09:32:29 PM »

If these guys are still around, it might be worthwhile to enlist them in the search.

I know they don't live up to Gary's expectations, but all we need from them are pairs of numbers.

They may even know something about where the Naval Observatory records went.
LTM,

           Marty
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« Last Edit: November 26, 2012, 09:36:34 PM by Martin X. Moleski, SJ »
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Jimmie Tyler

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Re: Can you add to the list of sextant numbers?
« Reply #145 on: November 27, 2012, 08:07:01 AM »

 I took the liberty of contacting Mr. Joel Jacobs,(Land and Sea collection). He actually responded within 1 hour of my inquiry. I have copied his responding e mail and am going to post it in this thread! I am going to ask him to overlook the Ameliapedia sextant data link, that I supplied to him. When he has time.

 I also am going to be contacting a friends father, whom was a Navy Captain for 27 years. It is worth the effort to see if he can, one help with the data table, or two supply information on the NO records. Also am working a time out to examine the antique collection of sextants. That I previously mentioned. Below is the responding e mail from Mr. Joel Jacobs from The Land and sea Collection.....

"Hi Jim,

 

Having an long term interest in aviation I am familiar with your org's work and applaud your efforts. We are very busy right now (Christmas Shopping Season) so I can't spend the time analyzing your comprehensive information, but we have one each example of a Brandis and a David White in stock.

 

See 1944 David White, http://landandseacollection.com/id888.html Very likely in the original case.

and a Brandis, Ca WW I see, http://landandseacollection.com/id858.html Likely not in the original case.

 

I have found that Naval Observatory numbers are not always in chronological sequence on clock dials. I have not compared them on sextants because the NO notation is only on the certificate. I have never seen an NO number on the instrument.

 

As far as the Brandis instruments there is a brief history of the company that we accumulated from many sources maybe some from your own org.

We agree that an original Brandis instrument would have the sextant serial number stamped on the box as well. IOO, this would likely be on the wood near a hinge and on opposing sides as in one of your pictures. They should be the same and match the quintant.

 

Thanks for your complement, but we are far from knowledgeable about this brand since this is the first instrument we've ever purchased for resale.

 

Let me know what you need further,"

 

Joel Jacobs

JOEL HARRY JACOBS, LLC

Land And Sea Collection

2287 SW Brookwood Lane

Palm City, FL 34990

772-287-7022

 

Visit our website: http://landandseacollection.com

 
Jim, TIGHAR #4064
 
« Last Edit: November 27, 2012, 08:42:22 AM by Jimmie Tyler »
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Martin X. Moleski, SJ

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Re: Can you add to the list of sextant numbers?
« Reply #146 on: November 27, 2012, 09:57:55 AM »

I took the liberty of contacting Mr. Joel Jacobs (Land and Sea collection). He actually responded within 1 hour of my inquiry.  ...

Thanks, Jimmie--much appreciated!

It sounds as though they have been dealing with a much later vintage of instruments than we have been tracking.
LTM,

           Marty
           TIGHAR #2359A
 
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Jimmie Tyler

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Re: Can you add to the list of sextant numbers?
« Reply #147 on: November 27, 2012, 10:58:33 AM »

I took the liberty of contacting Mr. Joel Jacobs (Land and Sea collection). He actually responded within 1 hour of my inquiry.  ...

Thanks, Jimmie--much appreciated!

It sounds as though they have been dealing with a much later vintage of instruments than we have been tracking.

  Yes that seems to be a fact!! I have exchanged a few e mails with Captain Jacobs, USMM-Ret. It is a good thing, in my opinion to have such a person aware of the Data Table. He may be of help in the future. I have asked Captain Jacobs to analyze the info. He seems to be a fan of TIGHAR and says he will gladly analyze the info on Ameliapedia, and respond to us as soon as he gets the time. Although he is not very knowledgeable on Brandis sextants, you never know when someone working in the field he does, will stumble upon a tantalizing piece of evidence, and think of us!!!  ;D
Jim, TIGHAR #4064
 
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Gary LaPook

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Re: Can you add to the list of sextant numbers?
« Reply #148 on: November 27, 2012, 06:52:37 PM »

If these guys are still around, it might be worthwhile to enlist them in the search.

I know they don't live up to Gary's expectations, but all we need from them are pairs of numbers.

They may even know something about where the Naval Observatory records went.

It's not that I had thought badly of them, it is only that it IS funny for them to have such a glaring error on their website and then to make the pompous claim of being the only knowledgeable people left when it comes to sextants. I pointed out this error to Mr. Jacobs, so that he could correct the error and "put his best foot forward" on his website, and got a vitriol filled email in return for my effort,  so NOW I do think badly of them.

gl

gl
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Gary LaPook

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Re: Can you add to the list of sextant numbers?
« Reply #149 on: November 27, 2012, 07:17:25 PM »

I took the liberty of contacting Mr. Joel Jacobs (Land and Sea collection). He actually responded within 1 hour of my inquiry.  ...

Thanks, Jimmie--much appreciated!

It sounds as though they have been dealing with a much later vintage of instruments than we have been tracking.

  Yes that seems to be a fact!! I have exchanged a few e mails with Captain Jacobs, USMM-Ret. It is a good thing, in my opinion to have such a person aware of the Data Table. He may be of help in the future. I have asked Captain Jacobs to analyze the info. He seems to be a fan of TIGHAR and says he will gladly analyze the info on Ameliapedia, and respond to us as soon as he gets the time. Although he is not very knowledgeable on Brandis sextants, you never know when someone working in the field he does, will stumble upon a tantalizing piece of evidence, and think of us!!!  ;D

Here is a link to a website belonging to a guy who DOES KNOW something about Brandis sextants.

http://sextantbook.com/?s=brandis

gl
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