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 1 
 on: October 20, 2018, 01:31:26 AM 
Started by Brian Tannahill - Last post by Martin X. Moleski, SJ
if sextant 1 (in box 1) is good but box 1 is bad, and sextant 2 is bad (but it’s box is still serviceable), you put sextant 1 in box 2 (making darn sure to relabel the box).  Does that make sense?

Yes, it makes sense, except not one of our mismatched boxes has been relabeled to match the sextants that they actually contain.

WE can tell the difference because we have come to understand some parts of the numbering system.

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#2.  Recall that a sextant is a precision instrument and each and every one is calibrated by the manufacturer (and subsequently recalibrated several times during its useful service life) to verify its accuracy (and they’re all inaccurate to some degree).  Their calibration corrections were recorded on a small serialized card and this card was either glued to the inside lid of the case, or kept in a small pocket built in to the case for that purpose.   The number on the card matched the number on the sextant; the card was for that particular sextant only and would never be used to correct the readings from another sextant as you would never be sure it had the same calibration errors.   As such, folks would be very serious about putting the sextant back into the correct box (with the proper correction card).

Yes, that should be the case (pun intended), but one way we figure out that there is a mismatch is by comparing the collimation slips with the numbers on the instrument itself.  I don't REMEMBER seeing a slip whose numbers did not match Brandis or NO numbers on the box.  I wasn't paying a lot of attention in the early years of this project, and I'm not sure we can double-check this.

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The important thing to remember is that a sextant is only as good as its accompanying calibration card.  Without the card for your specific sextant, you would never be sure of the accuracy and an inaccurate sextant can put your ship in the middle of the Sahara while you think you’re off the coast of Sicily (speaking for a friend...).

This is precisely what piqued my attention while working on the table: we have a lot of sextants in the wrong box with the wrong collimation slip.  It doesn't make sense.  But that is what our little study of a small sample of instruments shows.  Whether there was this same degree of confusion in the 1920s or 1930s is impossible to tell from this data.  We have some idea of present-day facts.  I don't think we know what correlation there might be between our statistics and the distribution of mismatched sextants in the old days.

 2 
 on: October 19, 2018, 08:28:31 PM 
Started by Brian Tannahill - Last post by Pat Fontaine
I’ll attempt to answer some of Brian’s questions-
The most likely reason sextants might wind up in the wrong box might be when they’re disposed of by the Navy.  At that point, they’re scrap and who cares?   Or if sextant 1 (in box 1) is good but box 1 is bad, and sextant 2 is bad (but it’s box is still serviceable), you put sextant 1 in box 2 (making darn sure to relabel the box).  Does that make sense?
Your question #1. How many sextants were found on a ship at?  It depends on the ship, but no ship had just one when that’s all you had to work your shots.  Smaller ships (escorts, destroyers, frigates and such) might have two or three.  One would be designated as ‘the’ navigator’s sextant, while others would be back ups, used to train others (used at the same time and the navigational results compared with the navigators, etc.).   Larger ships (carriers) might have five or six depending.  Most navigation departments I worked with in my Midshipman days would want to have several - above what the table of organization allowed the ship to have (sailors have a way of obtaining what they feel they need regardless of official regs).
#2.  Recall that a sextant is a precision instrument and each and every one is calibrated by the manufacturer (and subsequently recalibrated several times during its useful service life) to verify its accuracy (and they’re all inaccurate to some degree).  Their calibration corrections were recorded on a small serialized card and this card was either glued to the inside lid of the case, or kept in a small pocket built in to the case for that purpose.   The number on the card matched the number on the sextant; the card was for that particular sextant only and would never be used to correct the readings from another sextant as you would never be sure it had the same calibration errors.   As such, folks would be very serious about putting the sextant back into the correct box (with the proper correction card).
As for leaving it out of the box - sure.  It happened all the time, but never for long.  I remember often being with the navigator (aboard a frigate in the mid-70s) and he would remove the sextant and make sure it was working (had full range of motion,etc), add any necessary filters if he was shooting the noon sun, and we’d go take his shots.  Record the data and return to the chart table where he’d set it aside on the table while we worked the math.  If things worked out to his satisfaction, he’d put it away; if he had a problem or questioned the results, it was easy to go back out and shoot it again.
#3. Would the Naval Observatory switch boxes?  I suppose it would happen occasionally if a sextant was determined to no longer be useful or if the box was no longer useful (Navy doesn’t throw things out), but the box would be renumbered to match the sextant it contained and certainly the old correction card replaced with the one that corrersponded to the new sextant in the box.
#4.  Sextants, like other equipment, would often be removed from a ship.  It might be when the ship was in dry dock for extended periods, or if renovations/modifications were performed that required spaces to be emptied.  Battle damage, etc. also comes to mind.  They were also removed when ships were placed out of service.  They were not necessarily issued back to that same ship; a sextant that was issued for use on a destroyer might be turned in while the destroyer had battle damage repairs.  While turned in, it might/might not be recalibrated, and when issued might wind up on a carrier or submarine.  It just depended on the need and available sextants.  Sextants were assigned to ships (not individuals) based on the ship’s Table of Organization discussed in #1 above.  That said, it wouldn’t be out of the ordinary for a navigator to sign for and retain his own sextant (similar to when some officers were issued a service pistol as a Second Lieutenant and kept that same pistol until they were a General Officer).  I don’t believe this happened often.
I hope this helps.  The important thing to remember is that a sextant is only as good as its accompanying calibration card.  Without the card for your specific sextant, you would never be sure of the accuracy and an inaccurate sextant can put your ship in the middle of the Sahara while you think you’re off the coast of Sicily (speaking for a friend...).

 3 
 on: October 18, 2018, 11:45:27 PM 
Started by Brian Tannahill - Last post by Martin X. Moleski, SJ
If you read the items about the sextants that appear on the auction sites, you know that many or most of the sextants are not in their original boxes.  How did they end up in the wrong boxes?

"Many," yes.

"Most," no.

I created the new column on the table precisely so that we could get a better estimate (Wrong Sextant / Wrong Box) on the frequency of the mixups.

It is between 20% and 25%, as far as I can tell, for the sextants listed in our table.

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Here are some possible explanations.

We really need testimony from a navigator from that era, if any are still alive and well.  That's a long shot, I guess.  To serve in WW II, they would have had to have been born circa 1922-1927 and would now be in their 90s.  I'll bet most of the survivors aren't following this Forum.

 4 
 on: October 18, 2018, 09:02:31 PM 
Started by Brian Tannahill - Last post by Brian Tannahill
If you read the items about the sextants that appear on the auction sites, you know that many or most of the sextants are not in their original boxes.  How did they end up in the wrong boxes?

Sextant 4672, for example, is in the box for sextant 4667.  This is probably not important at all, but I'm curious how it happened.

Here are some possible explanations.


1.  Multiple sextants were were in use on a ship at the same time, and they were put away in the wrong boxes.

Probably not.  Was it common practice to use two or more sextants at the same time?  I'll defer to anyone who served on a ship, but I doubt it.

Does anyone know how many sextants would be found on a ship at sea?


2.  Sextants were left out of their boxes while not being used, and were eventually returned to whichever box was convenient. 

This doesn't seem likely.  I'd be surprised if regulations allowed storing sextants in whatever box was handy -- the military often takes minor details to an extreme.  Of course people don't always follow the rules.

Also, the military has a general culture of taking good care of important or expensive equipment.  Part of that would be to store the equipment properly.  Would a navigator make a practice of leaving a sextant sitting on a shelf or a tabletop between uses?  On board a ship at sea?  I'll defer to someone who's been there, but it doesn't make sense to me. 


3.  The Naval Observatory switched the boxes when sextants were sent in for calibration. 

Probably not, but who knows?  I can't rule this out.


4.  When ships were in port, the sextants were used off-ship for some reason (training?) and not returned to the correct boxes.

This is pure speculation.  It seems possible.  The navy guys are welcome to tell me I'm full of seawater on this one.

So, did sextants stay with a ship?  Or go with an individual?  Or something else?


5.  Sextants and boxes were mixed up after the navy released its surplus sextants following the end of World War I.  The surplus dealers and succeeding owners probably didn't care much about which box they used.

This sounds like the most likely explanation.

 5 
 on: October 18, 2018, 07:15:08 PM 
Started by Ric Gillespie - Last post by James Champion
The Morse code key in the cockpit picture shows two connectors under the key, and these appear to be the 1/4" phono plug type. There are a set of headphones draped over the seat armrest. So, it would seem that one is for the key and the other is for the headset - makes sense.

To have a CW/Voice switch on the cockpit control panel makes sense given the method of CW of that era. It is not quite the same CW that we're familiar with mid-WWII and afterwards, but technically MCW or Modulated CW. A tone-modulated AM signal was transmitted in MCW, and not just the AM carrier only. With pure CW, receivers needed a BFO or Beat Frequency Oscillator function (or other early CW reception feature) internally to add the tone to a CW signal being received. But with MCW, any AM receiver, older or newer, would receive the CW and provide an audible tone. This switch would activate the tone modulation circuits within the transmitter to create a MCW signal when the key was pressed. You wouldn't want the tone modulation to activate if you were actually using the microphone.



 6 
 on: October 18, 2018, 01:11:41 PM 
Started by Ric Gillespie - Last post by Ric Gillespie
Anyone have the TO&E for a LORAN unit?

That's Table of Organization & Equipment for you civilians.  Every military unit has one. How many people, what kind of people, what kind of stuff, and how much stuff you're supposed to have (and rarely do).

 7 
 on: October 18, 2018, 12:49:00 PM 
Started by Ric Gillespie - Last post by Bill Mangus

Closer than anything we've seen on the Electra.  Seems like a 16mm projector would be a common standard issue item for military units.  Somebody knows.  Some museum probably has one.
The way you identify an artifact is to find a known thing that looks just like the unknown thing.


Looking . . . have a couple of feelers out . . . see if I get a response.

Anyone have the TO&E for a LORAN unit?
 ;D

 8 
 on: October 18, 2018, 12:05:45 PM 
Started by Ric Gillespie - Last post by Ric Gillespie
A hundred yards from the house to the north was the radio station

The radio shack was still standing and basically intact when we started visiting Niku.  All gone now.

 9 
 on: October 18, 2018, 11:56:28 AM 
Started by Ric Gillespie - Last post by Martin X. Moleski, SJ
It seems to me that there various kinds of radio stations on Niku at different times.  I think it would be hard to eliminate all of them as possible sources of the connector. 

From “Nikumaroro” by P. B. Laxton:

"They rose before dawn each day, and after the early light meal, went out under the leadership of Tem Mautake to the bush for clearing and planting. Gallagher would make his radio schedule, deal with the little office work, and follow the working parties with the native leader and acting Magistrate, Teng Koata and with his personal “boy,” young Ten Aram Tamia, a Gilbertese educated under Major Holland, G.C., at the Colony’s King George V school at Tarawa."

"The terrific impact of German and Japanese aggression and global war threw Nikumaroro into the background, and no resident officer replaced Mr. Gallagher. In 1943, however, a survey party came, and thereafter a radio navigation station was set up by the United States Forces."

"The acting Island Magistrate was that same Aram Tamia who had accompanied Gallagher as his houseboy. Next day I set out with him on a tour of inspection. A hundred yards from the house to the north was the radio station, under charge of Ten (or Mr.) Tekautu, a skillful, English-speaking, Gilbertese wireless operator. He kept a daily “Met. log” which he transmitted to Canton Island, making also two other daily schedules for official business and private telegrams. His equipment, old and needing replacement, was well and intelligently maintained. Tekautu was unmarried and a little lonely, since he was not a Nikumaroro man."


 10 
 on: October 18, 2018, 11:34:08 AM 
Started by Ric Gillespie - Last post by Ric Gillespie
Second picture (not terribly well focused) shows external speaker connection cable.  Looks close to Joe's find ?

Closer than anything we've seen on the Electra.  Seems like a 16mm projector would be a common standard issue item for military units.  Somebody knows.  Some museum probably has one.
The way you identify an artifact is to find a known thing that looks just like the unknown thing.

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