Advanced search  
Pages: 1 ... 5 6 [7] 8 9 ... 33   Go Down

Author Topic: Can you add to the list of sextant numbers?  (Read 338449 times)

Andrew M McKenna

  • Administrator
  • *
  • Posts: 637
  • Here I am during the Maid of Harlech Survey.
Re: Can you add to the list of sextant numbers?
« Reply #90 on: April 25, 2012, 03:13:17 AM »

Vendor replies the manufacturer's number on the arc is 3331. The number on the box is 4551. As before the NO is 1421.

Clarification from the owner.  The actual sextant has Brandis #3331 and USNO # 1421 on the arc.

The box has 4551 stenciled on the box near the hinge, and NO # 1762 on the label.

So we're talking about two different sets of numbers here,  B 3331 / NO 1421, and B 4551 / NO 1762.  #3331 is simply in the wrong box, which we've seen frequently in the past. 

Marty, we should be able to log both sets on the table, yes? 

Both match the pattern pretty well.

Andrew
Logged

Martin X. Moleski, SJ

  • Administrator
  • *
  • Posts: 2934
Re: Can you add to the list of sextant numbers?
« Reply #91 on: April 25, 2012, 06:31:01 AM »

So we're talking about two different sets of numbers here,  B 3331 / NO 1421, and B 4551 / NO 1762.  #3331 is simply in the wrong box, which we've seen frequently in the past. 

Marty, we should be able to log both sets on the table, yes? 

Yes.  This is the fourth mismatch in our table.
LTM,

           Marty
           TIGHAR #2359A
 
Logged

richie conroy

  • T5
  • *****
  • Posts: 1412
Re: Can you add to the list of sextant numbers?
« Reply #92 on: June 03, 2012, 10:08:24 AM »

just come across this sextant says on label No 3567 i think http://www.pielcraftsmen.com/gifts/artifacts/instruments.html

go to bottom of page on link 
We are an echo of the past


Member# 416
 
Logged

Walter Runck

  • T3
  • ***
  • Posts: 117
Re: Can you add to the list of sextant numbers?
« Reply #93 on: June 30, 2012, 08:18:46 AM »

You can add 3985, but I'd like someone to confirm the NO number as 1826.  It's on eBay and the listing says NO 4829 but I believe the 4 is a stylized 1 and the 9 is just a mistake. 

Nice unit, looks complete including some tools I have not seen before.  Box in better shape than most, but no evidence of collimation cert on inside of cover.  Numbers I suggested are in general conformance with the pattern, although a minor conflict with 4551, which I believe was just a box with a non-matching sextant in it.

Sorry for typos, I'm a little out of forum practice. 
« Last Edit: July 04, 2012, 06:44:38 AM by Walter Runck »
Logged

Bruce Thomas

  • Administrator
  • *
  • Posts: 646
  • Now where did I put my glasses?
Re: Can you add to the list of sextant numbers?
« Reply #94 on: June 30, 2012, 10:14:36 AM »

You can add 3985, but I'd like someone to confirm the NO number as 1826.  It's on eBay and the listing says NO 4829 but I believe the 4 is a stylized 1 and the 9 is just a mistake. 

Nice unit, looks complete including some tools I have seen before.  Box in better shape than most, but no evidence of collimation cert on inside of cover.  Numbers I suggested a in general conformance with the pattern, although a minor conflict with 4551, which I believe was just a box with a non-matching sextant in it.

Walter, you're right about the last digit of the NO number being a 6.  The picture of the sextant arc bears that out, and whoever typed the narrative on eBay just had a "finger fault."  I'm going to enter it into our Ameliapedia table as NO number 4826; I have a Brandis sextant in my den, and the NO number is engraved on its arc -- obviously done by the same hand, with the leading digit for it very clearly a 4 as well.
LTM,

Bruce
TIGHAR #3123R
 
Logged

Andrew M McKenna

  • Administrator
  • *
  • Posts: 637
  • Here I am during the Maid of Harlech Survey.
Re: Can you add to the list of sextant numbers?
« Reply #95 on: July 01, 2012, 02:27:22 AM »

Looks like this latest sextant - Brandis 3985 / Navy 4826 is back on ebay.

The price is way out of whack, these usually go for between $300 and $400

amck
Logged

Andrew M McKenna

  • Administrator
  • *
  • Posts: 637
  • Here I am during the Maid of Harlech Survey.
Re: Can you add to the list of sextant numbers?
« Reply #96 on: August 20, 2012, 08:49:35 AM »

There is another Brandis on ebay, #5084.  I can't tell if there is a USNO number from the photos, and I've sent a question to the seller.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=251134812762&ssPageName=ADME:B:SS:US:1123#ht_1453wt_1144

Andrew
Logged

Bruce Thomas

  • Administrator
  • *
  • Posts: 646
  • Now where did I put my glasses?
Re: Can you add to the list of sextant numbers?
« Reply #97 on: August 20, 2012, 10:11:04 AM »

There is another Brandis on ebay, #5084.  I can't tell if there is a USNO number from the photos, and I've sent a question to the seller.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=251134812762&ssPageName=ADME:B:SS:US:1123#ht_1453wt_1144

Andrew
The narrative says that number 5084, but the photo (upside down) has it inscribed as 5804.

Update:  I see that the eBay listing's narrative has been modified to state that the number is 5804.    (8/24/2012)
LTM,

Bruce
TIGHAR #3123R
 
« Last Edit: August 24, 2012, 05:54:37 AM by Bruce Thomas »
Logged

John Kada

  • T3
  • ***
  • Posts: 110
Re: Can you add to the list of sextant numbers?
« Reply #98 on: August 28, 2012, 01:19:20 AM »

The Ameliapedia page on the Sextant Box has a Chart listing  U.S. Naval Observatory Numbers, manufacturer numbers and Eccentricity Certificate dates for a number of sextants that have turned up in museums, ebay, etc. Following the chart is a discussion by Ric and Art Rypinski about (perhaps I’m simplifying) what those numbers might imply about when a sextant with Gallagher’s numbers (3500/1542) might have last passed through the Naval Observatory.

Art, citing the Smithsonian, says that that the manufacture of Brandis instruments ceased in 1932 and goes onto say that “ …it would be reasonable to believe that almost all of the Brandis sextants in circulation were actually manufactured in 1918-1920, and that none were manufactured after 1932. Further, the Naval Observatory appears to have changed its numbering plan (at least for aviation octants) in the late 1920s, and begin issuing NO numbers with the form XXXX-YY, where YY was the year of original calibration. Therefore, I believe that all of the post-1930 calibration dates are recalibrations of sextants that were originally calibrated and issued their NO numbers in 1918-1920…”

Looking at the numbers in the chart, I couldn’t follow why Art thinks the Naval Observatory changed its numbering plan in the late 20s to use a six digit i.d. code: the only sextants I see on the chart with six digit ids have certificates dating from the 40s. But I do think the  numbers in the chart suggests that Art is right about most sextants having been manufactured in right around WWI and that some of these sextants were later given new eccentricity certificates.

I don’t have a deep statistical analysis to present, but I do think it is interesting to forget about the manufacturer’s numbers and look at the frequency of distribution of Naval Observatory numbers and certificate dates as shown below:
                    # of     
N.O #          Sextants    Date Range (# of certs)
0 to 999               7             1918 to '43 (3)
1000 to 1999      17             1918 to '42  {8)
2000 to 2999       9             1919 to '46 (6)
3000 to 3999       0                    N/A
4000 to 4999      14             1938 to '44 (3)
5000 to 5999       5             1945 to 1945 (2)
g.t. 6000              2             1946 (1)

The second column of numbers shows how many of the 54 sextants in the Ameliapedia chart fall into each of the seven Naval Observatory number ranges. The third column then gives the range of certificate dates for the sextants in each range, and the numbers in parentheses gives the number of certificates in each range. Have I lost anybody yet ?...

A couple of things are interesting when the numbers are viewed this way: 

-We see certificates ranging from 1918 to the mid-40’s for sextants in the first three ranges of Naval Observatory numbers, i.e. numbers less than 3000; A simple explanation is that sextants having these N.O. numbers were produced around WWI, and some of them remained in service in the Navy and received new eccentricity certificates many years later. This is consistent with Art’s remarks about re-certification of sextants the Ameliapedia discussion.

-We don’t see any WWI vintage certificates in the last three N.O. number ranges, i.e. those greater than 4000; A simple explanation is that the USN didn’t start assigning sextants with numbers greater than 4000 until WWII was looming. Note however that back on the main Ameliapedia chart many Brandis sextants have N.O. numbers in the 4000-4900 range. Art tells us that Brandis stopped making sextants in 1932, and Art (I think correctly) believes that most of the Brandis sextants are of WWI vintage (the Navy had a glut of sextants after WWI, so it doesn’t seem likely they would have been buying more Brandis sextants from 1919 to 1932 the year of Brandis’s demise).

Maybe the Navy stockpiled unused WWI-vintage sextants that never got  N.O. numbers assigned to them and pulled ‘em out of storage for use in WWII?  I don’t like that explanation much, but it would explain things…

- We don’t see any sextants with N. O. numbers in the 3000 range. Assuming this isn’t a statistical fluke, the only simple explanation for the gap in numbering that I can think of is that for some reason no sextants were ever given N.O. numbers in the 3000-3999 range. Maybe the Naval Observatory misplaced its master list of sextant numbers after WWI, and when WWII started to loom some old fart in the eccentricity shop remembered they left off numbering sextants somewhere in the high 2000s? Another not so great explanation…

If this post is total nonsense, please forgive me—it’s 3 AM and maybe I’m not thinking straight…

----------------
note added: I hope to get another post up soon about the sextant numbers which I think may make the absence of and 3000-series sextants seem even a bit odder than it seems now...
« Last Edit: August 28, 2012, 02:14:08 AM by John Kada »
Logged

John Kada

  • T3
  • ***
  • Posts: 110
Re: Can you add to the list of sextant numbers?
« Reply #99 on: September 13, 2012, 09:33:53 PM »

It appears that my last post on three sextants to possibly add to the list fell victim to the great wipe-out, so I’ll try to reconstruct my post.

This site lists a recently sold Heath Hezzanith Sextant. According to the seller, the sextant can be dated to before 1900 by its design. There is a photo of the USNO collimation certificate, dated August 9, 1945, with the sextant identified as H.G. (high grade). The number after (N) on the certificate, 6416, should be the USNO number and the the vendor says that on the left end of the arc is the number 9416 preceded by a 9. Flip that upside down and what do you get?...hmmn...

An ebay auction with 2 days to go is for a sextant with a USNO certificate dated June 1, 1925 for USNO sextant 27 (the certificate originally had it list as number 25, but the ‘5’ is crossed out in red and a ‘7’ written in above it). The certificate identifies this one as a surveying sextant. The arm of this sextant has the number ‘252187’ engraved into it.


This site lists what it calls a “US Naval Observatory BU Mark II” sextant made by David White. It says the sextant was used on the bicentennial voyage of the Bounty!  A blurry photo of the certificate, dated 9/25/1942, indicates a N.O. number of  3320-41, and the ‘class’ as “E.T.S.”; I’m not sure what that means.

Tonight I found a fourth sextant, a Keuffel & Esser, on ebay The certificate for this one, dated 10/19/42, indicates it is a surveying sextant. This certificate has a place on it marked “No.”, which to me looks like where the manufacturer’s number should go: here there is no number, just has a horizontal line marked in ink. There is also a place on the certificate marked “Sextant (N)”, and here the number 4730 is written in ink. On the three previously mentioned sextant certificates, one would expect the number next to the (N) to be a Naval Observatory number, but here with the K&E sextant that can't be: there is a photo of the arm of the K&E sextant, and stamped there is “Keuffel & Esser Co. New York 4730”. So it looks like the number next to the (N) on the certificate for the K&E sextant is the manufacturer number rather than the USNO number (unless by some freakish chance the two numbers  coincided).

Perhaps by now Tighar High Command has ebay and some of these other vendors staked out and so these sextants are old news, but thought I'd post before the sextants disappear from view for a couple of more decades...


« Last Edit: September 13, 2012, 11:23:05 PM by John Kada »
Logged

John Kada

  • T3
  • ***
  • Posts: 110
Re: Can you add to the list of sextant numbers?
« Reply #100 on: September 21, 2012, 06:16:41 PM »

Over on the Who Did the USN Give its Surplus Sextants To? thread I posted a link a site where USNO Annual Reports are available for download and/or viewing.

At the end of each year's report is a table of results of tests done on chronometers. torpedo boat watches, etc. Many of these tables were improperly copied and are unreadable in the downloadable pdf for the FY 1916-1930 reports but the table listing test results for what looks to be the 1920 fiscal year USNO report are readable (look at page ~137 of the 395 page downloadable pdf for FY 1916-1930). What is interesting here in these tables is that in several places, 'old' chronometers and watches have what appear to be Naval Observatory numbers; no 'new' chronometer or watch does. The 16 or so  Naval Observatory numbers are all in the 4000 to 5000 range and none of them duplicate those of sextants that we know of.

Did the USNO keep parallel numbering schemes for sextants and torpedo boat watches/chronometers, or were these different instruments all part of a single numbering system? It would be good to know more about this- for instance, if there was a single numbering system incorporating sextants, torpedo boat watches, and chronometers then readable copies of the tables of the torpedo boat/chronometer tests might tell us something about when N.O.  #1542 was assigned to a sextant at the Naval Observatory. Then again, we might discover that N.O.#1542 was assigned to a chronometer, not a sextrant, with inplications for the numbers Gallagher reported for the sextant box found on Gardner.

-----------
update: a quick google search turned up this: http://forum.atgvintagewatches.com/showthread.php?t=1975

USNO 847 Waltham serial number 22115845 on the movement, which this table says is a 1918-1919 chronometer (but I've seen comments on horology web sites saying that tables of manufacturer serial numbers are for some manufacturers (not necessarily Watham), only good to within a few years...
« Last Edit: October 01, 2012, 10:39:48 PM by John Kada »
Logged

Ricker H Jones

  • TIGHAR member
  • *
  • Posts: 112
Re: Can you add to the list of sextant numbers?
« Reply #101 on: September 21, 2012, 09:24:20 PM »

An interesting Brandis ad in Rudder magazine states "2400 furnished by us to the U.S. Navy Department during the period of the war." The same ad also states "prices lower than paid for inaccurate second-hand sextants." perhaps referring to a glut of surplus sextants on the market at the time.  I believe this issue of Rudder was published around 1921, but I was unable to locate the magazine again.  (It may have been in the U of Michigan library.)
Logged

Alan Harris

  • T3
  • ***
  • Posts: 137
Re: Can you add to the list of sextant numbers?
« Reply #102 on: September 21, 2012, 10:05:04 PM »

I was unable to locate the magazine again.  (It may have been in the U of Michigan library.)

You are correct, Ricker, the original is in the Wolverine library.  The Rudder, Vol. 35, 1919.
Logged

John Kada

  • T3
  • ***
  • Posts: 110
Re: Can you add to the list of sextant numbers?
« Reply #103 on: September 23, 2012, 07:33:45 PM »

Ricker,

Looking at the Ameliapedia sextant table, the difference between highest and lowest Brandis numbers of sextants thought to have USNO numbers is 5760-2734=3026.  So, to the extent that the range in sextant numbers in the Ameliapedia table indicates the number of sextants produced by Brandis during WWI, something like 600 (i.e. ~3000 minus ~2400) Brandis sextants went to other customers during WWI.

That's interesting because at the outset of WWI, the USN was faced with a shortage of many types of equipment due to the fact that most of the optical glass used in nautical instruments was imported from Europe. This shortage is discussed in USNO Annual Reports of the era and I alluded to it in a post on the Who Did the USN Give its Sextants to after WWI thread. Navy Secretary Franklin D. Roosevelt launched the ‘Eyes of the Navy’ to solicit donations of nautical equipment from the public, and while the focus of the program was to obtain binoculars, telescopes, and spyglasses to help ships watch for U-boats, the USN did apparently receive at least some sextants via this program. An indication that the optical glass shortage impacted the USN’s demand for sextants is seen in the USNO Annual Report for 1917, which tells us that the observatory’s nautical instrument repair shop built 60 Frankensextants from junked sextants it had on hand (they didn't use the term 'Frankensextant', of course...). So it is interesting that customers other than the USN were able to get sextants from Brandis during the WWI era given this shortage. By war’s end the optical glass shortage problem had been solved, so maybe the supply loosened up by 1918 or so?...

If for no reason other than the fun of it, one can come up with an estimate of the total number of USNO numbers issued during WWI from the Brandis ad with a little help from the Ameliapedia sextant table.  The table lists 38 Brandis real or putative (i.e. only box) sextants with USNO numbers out of a total of 53 sextants. But the last 6 of the 53 (the Merganthalers and David Whites) look to be post-WWI, so let’s say 38 out of 47, or 80% of the sextants are Brandis models. That would suggest that 2400 x (100/80)=3000 USNO numbers were issued during WWI.  Over on the 'Who Did the USN Give...' thread I came up with an estimate of 4600 for the number of USNO sextants issued based on information gleaned from the USNO annual reports of the era. (I still need to make a post to explain this 4600 guesstimate of mine). Not the greatest agreement but someone with a better grasp of statistics could easily say whether the latter estimat is really different from 4600 at a high confidence level...

Finally, you speculated that there might have been a glut of surplus Navy sextants by the time this Brandis ad appeared. The first indication I could find of the Navy disposing of sextants after WWI was in 1928. I certainly wouldn’t want to bet that the sextants weren’t surplussed by 1919, but I didn’t see any mention of it in the USNO Annual reports for what it’s worth.


« Last Edit: September 23, 2012, 08:29:43 PM by John Kada »
Logged

John Kada

  • T3
  • ***
  • Posts: 110
Re: Can you add to the list of sextant numbers?
« Reply #104 on: September 24, 2012, 12:16:10 AM »

In reply #98 above I made a table showing the frequency distribution of eccentricity certificates with Naval Observatory number.  There I said:

We see certificates ranging from 1918 to the mid-40’s for sextants in the first three ranges of Naval Observatory numbers, i.e. numbers less than 3000; A simple explanation is that sextants having these N.O. numbers were produced around WWI, and some of them remained in service in the Navy and received new eccentricity certificates many years later”.

While the idea that the USNO re-calibrated WWI-era sextants seemed like a reasonable way to explain the pattern of eccentricity certificate ages apparent in the table, I was not totally comfortable with this idea. My understanding of the eccentricity certificates is that they were provided with sextants so that a navigator could correct for systematic deviations between true and measured angles due to the fact that the pivot point of the arm of the sextant isn’t quite at the center of the circle of the sextant’s arc. This reference states that ‘permanent adjustments’ such as eccentricity “with careful use will never be deranged”, and also, that errors due to eccentricity “should be determined once for all at some place where proper facilities for doing the work are at hand”. So eccentricity corrections seemed only to need to be determined once, a fact at odds with the ‘simple explanation’ I offered.

The 1919 Annual Report has a table that indicates that 2351 new sextants were inspected and passed. Directly following this table is a statement that reads “ 3136 new and repaired sextants were tested for eccentricity”. So for 1919 we know that 785 (i.e., 3136-2351) repaired sextants were tested for eccentricity. So based on this report I’m thinking my ‘simple explanation’ is correct, and that whenever a sextant came back to the USNO for a ‘repair’, out of prudence the USNO re-measured its eccentricity and issued a new eccentricity certificate to replace the one previously issued.

The Annual Reports from 1923 -1929 all have a statement along the lines “Owing to the supply at hand practically no new instruments were purchased.” So from 1923 till 1929 the USN was not adding to its sextant stock but during this period the annual reports tell us that the observatory was still repairing sextants. About 780 of them were repaired between ’23 and ’27, in fact. If the USNO kept repairing sextants at this rate into the 1930’s and it issued new eccentricity certificates to these sextants before returning them to the fleet, then it is no surprise that a significant fraction of the (putative) WWI era sextants we know of have eccentricity certificates dating from the era between the two world wars.
« Last Edit: September 24, 2012, 12:34:44 AM by John Kada »
Logged
Pages: 1 ... 5 6 [7] 8 9 ... 33   Go Up
 

Copyright 2018 by TIGHAR, a non-profit foundation. No portion of the TIGHAR Website may be reproduced by xerographic, photographic, digital or any other means for any purpose. No portion of the TIGHAR Website may be stored in a retrieval system, copied, transmitted or transferred in any form or by any means, whether electronic, mechanical, digital, photographic, magnetic or otherwise, for any purpose without the express, written permission of TIGHAR. All rights reserved.

Contact us at: info@tighar.org • Phone: 610-467-1937 • Membership formwebmaster@tighar.org

Powered by MySQL SMF 2.0.15 | SMF © 2017, Simple Machines Powered by PHP