This is going to be a long post. According to
a brief history of Brandis given on the Smithsonian web site, Brandis slightly changed its name three times during its existence and therefore the way the Brandis company name is marked on a sextant can potentially tell us something about when it was manufactured.
“Frederick Ernest Brandis (1845–1916) was born in Germany, came to the United States in 1858, worked for Stackpole & Brothers for a few years, and then opened his own instrument shop in 1871. The firm became F. Brandis & Co. in 1875, F. E. Brandis, Sons & Co. in 1890, and Brandis & Sons Mfg. Co. in 1916. The Pioneer Instrument Company purchased control of Brandis in 1922, and sold it to the Bendix Aviation Corporation in 1928. The manufacture of Brandis instruments ceased in 1932.”
So, we have three Brandis eras:
The ‘F. Brandis & Co.’ era, from 1875 to 1890;
The ‘F. E. Brandis, Sons, & Co.’ era, from 1890 to 1916;
The ‘Brandis & Sons Mfg. Co.’ era, from 1916 to 1932.
I checked all of the sextants in the Ameliapedia table that had active ebay links and also the Brandis sextants in the Smithsonian’s collection to see how the Brandis name is marked on those sextants. What I found is summarized in Table 1. In the first three columns I’ve listed the Naval Observatory number, the Brandis serial number, and the wording of the Brandis name stamped into the sextant; some of these name markings I could read myself while in other cases I had to rely on what is stated by the vendor or by the Smithsonian. Most of the ebay vendors are clear enough in their descriptions that I think the information in the table is accurate, but I provide the caveat that the name descriptions provided for NO #1146 and NO 4485 are a bit vague; there used to be photos of #4485 on the vendor’s web site that might have allowed us to read the name ourselves, but unfortunately the pictures have been removed.
Note that I’ve also included in Table 1 three sextants for which I have incomplete information. These are the
1918 Mt. Baker eclipse observation party sextant (Brandis #3257), a sextant listed in the Ameliapedia table (N.O. number #2975) that was used on a seaplane flight across the Atlantic Ocean in 1919, and a sextant in the Smithsonian’s collection (Brandis # 3193); the partial information available for these sextants still makes them worth including here.
All of the sextants for which there is name information are of the ‘Brandis & Sons Mfg Co.’ type and thus it would appear they were manufactured no earlier than 1916, and thus 1916 would seem to be the earliest year that these sextants could have been given their Naval Observatory numbers. Since Brandis stopped making sextants by 1932, we can confidently say that they were given their N.O. numbers no later than 1932, but I think we can assign an even earlier ‘no later than’ date with reasonable confidence based on what the Naval Observatory annual reports tell us. The annual report for 1919 tells us that the US Navy had a glut of navigational equipment on hand after the armistice and therefore
as discussed here, the Naval Observatory transferred some of its unneeded navigational equipment to the merchant fleet. This suggests to me that the USN didn’t have a need to buy many of sextants after 1919, and what I read in USNO annual reports published after 1922 bears this out (unfortunately I don’t have the ’21 and ’22 annual reports). The 1922 USNO Annual Report indicates that 100 new ‘high-grade’ sextants were purchased that year and reports for the years 1923-1927 consistently say something along the lines of “Owing to the supply at hand practically no new instruments were purchased”. The 1928 annual report tells us a large quantity of navigational equipment was transferred from the Naval Observatory to the Washington Navy Yard to be sold as surplus. It isn’t until the USNO Annual Report of 1931 that there is once again a mention of new sextants being purchased, but even then only 20 of them. I think, based what the USNO tell us, it is reasonable to assume that few Brandis sextants were purchased by the Navy after 1923 and therefore it is reasonable to assume that nearly any Brandis sextants we're likely to see was assigned its N.O. number no later than 1923. We can assign even earlier ‘no later than’ dates to several of the sextants in Table 1 because we have additional information about their whereabouts. Three of them have eccentricity certificates dated earlier than 1923 (see the fourth column of table), hence these three sextants must have been given their N.O. numbers no later than the year indicated by their eccentricity certificates. The ‘no later than’ year of the sextant used by the 1918 Mt. Baker eclipse observation party can be safely assumed to be 1918. Combining the ‘no earlier than’ and ‘no later than’ dates worked out above gives us the date ranges listed in column 5 for assignment of N.O. numbers to these sextants.
Note that the table lists three Brandis surveying instruments that are in
the Smithsonian’s collection of surveying instruments; these instruments don’t have N.O. numbers but they do have Brandis serial numbers and it is interesting to see how their serial numbers and dates of manufacture fit in with those of the sextants (see note below the fold). The Brandis surveying instruments appear to pre-date any of the sextants and all three of them have N.O. numbers that are less than those of any of the sextants, as one would expect if there was a single serial number series for all of Brandis’ products.
Table 2 (attached) consolidates the N.O. numbers and dates of the Brandis sextants with those of the six Keuffel & Esser sextants from the Keuffel&Esser production dates table in Ameliapedia; there is also a Buff & Buff sextant which I include because it has a N.O. number (#1065) and can be given a ‘no later’ date of 1918 based on its eccentricity certificate.
A fairly consistent picture seems to emerge for the chronology of issuance of Naval Observatory numbers. It looks like the Naval Observatory number series increased very slowly prior to WWI, reached the 600s in 1916, and then rapidly increased to at least the low 3000’s by 1918 and the high 4700s by no later than 1923. This chronology agrees nicely with the arrival of the tsunami of new sextants for eccentricity testing 1918-1919 that
we learn from the USNO annual reports .
Placing 1542 and 3500, pair of numbers that Gallagher reported on the sextant box found with the castaway’s remains, in the appropriate place in this table, it appears that if Gallagher’s sextant box once held a USNO sextant it was assigned its N.O. number in 1918 or 1919 and therefore this would be the earliest that our castaway could have arrived at Gardner.
As for the Brandis serial numbers, I would guess that before 1918, there was a fairly monotonic increase in Brandis serial number with N.O. number. My thinking is that until 1918, the rate of delivery of new sextants to the Observatory was fairly low and the observatory was assigning N.O. numbers to sextants essentially as quickly as they arrived from the manufacturer. But then in 1918 the Naval Observatory got slammed with the tsunami of sextants, creating a backlog of sextants in crates a warehouse somewhere; the Naval Observatory staff worked through this backlog, pulling crates out of the warehouse in no particular order with respect to sextant serial numbers. Thus a large number of Brandis sextants were assigned N.O. numbers in 1918 and 1919 with no correlation between the N.O. numbers and the Brandis serial numbers. I think we might see a fairly monotonic increase in N.O. number with Brandis serial number for N.O. numbers less than ~700, and I’d expect to see a fair number of sextants marked ‘F.E. Brandis, Sons, & Co.’ among them.
The Ameliapedia table has a Brandis sextant with NO number 362 and Brandis number 2734; if there was a monotonic increase in N.O. number with Brandis number prior to 1918, then a sextant with the N.O number 173 (the putative N.O. number of the sextant written on the Pensacola sextant box) would have a Brandis serial number that was less than ~2700, a good deal lower than the 3547 that is written on the Pensacola box. One or both of the two numbers has some other meaning.
I suspect that Tighar members might be able to check Brandis markings on some of the other sextants listed in the Ameliapedia table. It would be nice to know how the manfacture dates, N.O. numbers and Brandis serial numbers of these other sextants fit in with the chronology I’ve developed here. I’d be particularly curious to see how the sextants with N.O. numbers 362 and 845 are marked; my guess based on the trend in N.O. number with date we see in the second table is that NO #362 is old enough to be marked ‘F.E. Brandis, Sons, & Co’, while NO#845 is a sextant made in the ‘Brandis & Sons Mfg. Co.’ era.
===================the fold===============
Note on the Brandis surveying instruments: the Smithsonian says that the surveying instrument with Brandis serial number #1065 is marked ‘Brandis Manufacturing Company’, but if you look carefully at the photo of the box (the image is reversed) it reads “F.E. Brandis, Sons & Co.” thus it is of 1890-1916 vintage.