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Exceptionally Rare & Historically Important Micrometer by PALMER

Who invented the first micrometer?
It was Palmer.

Ok, fire away!

No fire from me!

Alexander Graham bell didn't invent the telephone - he was the first to get to the patent office. Literally, by hours, IIRC.

Ford didn't invent the automobile. He popularized it (depending on your definition of automobile, you could argue Daimler or Cugnot).

The British "discovered" radio before Marconi, but they didn't know what it was (actually, Tesla was before Marconi, according to the US Supreme Court).

Edison didn't "invent" the light bulb, he's just the guy that got the thing to work well and last.

How you define "it" will determine who invented "it".

This has been an interesting post. Love reading the history.

It's a pity the word invented was ever ..... for want of a better word, invented.

As SteveM suggests, we first need to be clear about the object in question.

I think we have two separate principles here, both of which can be regarded as original devices: First, the principle of making a measurement using a screw with a graduated angle of rotation, i.e. using the pich of a screw as a measurement unit, and having a circular scale to give sub-divisions of the pitch, the first recorded example being due to Gascoigne; second, the use of this principle in a simple, robust and portable intrument, for which the evidence clearly points to Palmer as the originator.
First you have the inventor -Look at this keen idea!
Then you have the developer - Interesting idea. How can I make it useful and marketable??? Aha!
I think the micrometer caliper pioneered by M. Palmer is clearly the first in the line of a tool that has become the defining mark of a machinist. It is the iconic status of the micrometer that make 'first' interesting. We wouldn't have nearly as much debate if it were a less iconic tool: how much would we discuss the first height gage?

I think the diamond-studded micrometer mentioned in another thread illustrates the iconic status of the micrometer. Watts bench mic, Maudslay's "commander" and Gascoine's telescope do not share that iconic status.

We can quibble about definitions, but it's seems pointless. Palmer's tool is distinct from the bench micrometers that preceeded it and is like the micrometers that are still in use today.
How was it made?

From the photos presented, I would tend to believe that the blank that the mic was made from was first forged to shape before being machined/filed to finish. The part would probably have been forged using a spring die to get the "keyhole" shape after having the offset done with some type of offset die or even done with a simple bending jig. The part that someone said would be thinner (the outside of the frame corners) appears to have been milled(filed) down.

I am still thinking about how this was made...... if forged, at what point would you drill the hole for the threaded spindle? It seems to me that at this period drilling a hole that deep that is straight would be a pretty hard thing to do...... remember Morse's twist drills had yet to be invented and spade drills are not great for deep holes....... what did gun drills look like at that time? One detail I have yet to check is if the two holes line up and were threaded in the same pass of a tap...... I have to get a treaded rod of this size and see if it screws in both.

I know very little about forging, what is a spring die?
I agree that the hole is the real question. Whether it was forged or cut doesn't change the challenge of lining everything up. The bore needs to be centered in the barrel as well, so as not to interfere with the thimble.

fen2art, the thickness of the C-part of the frame is exactly the opposite of what you would see if it were bent; it is thickest on the outside of the bend. I agree about a die for the keyhole shape, but it looks to me as though forging the entire frame to shape would generate more benchwork than cutting the frame out of a keyhole shaped bar.

Rivett, here is a picture of a spring swage, it combines what would traditionally have been top and bottom anvil tools into a single tool. The one in the picture is a little crude, but there were few pictures showing the spring-handle. These can be made with various dies in the business end, and making a pair of swages to produce our keyhole profile would be a fairly simple task. The second image shows a pair of swages used to forge a profile in a bar.

Sorry it should be called a spring swedge


The proper name for the tool I was referring to is a spring swedge...essentially a top and bottom die connected by a spring.

Here is a catalog showing some modern commercially available spring swedges.https://www.blacksmithsdepot.com/page.php?theLocation=/Resources/Product/SWAGE_spring

I hadn't considered drilling technology available at the time...could have been done like a gun barrel (forged/welded around a mandrel) or like the guide tube on an old style lock key (formed from flat stock and forge welded into place.) I don't know when twist drills were invented but would think they predate this mic.

If bent prior to swedging the section in the mic is easily obtainable.

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Looks like we posted the spring swage at the the same time.

I'm hesitant to bring this up in light of my recent temporal inconsistencies, but I think the forging techniques you're describing are for earlier work than this and more appropriate to the American frontier than cosmopolitan Paris.

I'm trying to do a little more research before I make any declarative statements. I've ordered a couple of books on french working class and conditions, so hopefully I can start to get an idea of what they would have had in an instrument making shop in Paris in 1848.

I'm getting these
The French worker: autobiographies ... - Google Books

Taking the hard road: life course in ... - Google Books

I'd be interested in recommendations for books addressing industrial development and organization rather than personal stories. I suspect that sort of history is not in the popular press.
It has been confirmed by the CNAM that they do not have a Palmer micrometer but the do have some other Palmer related objects, maybe more on that later but we will not see photos due to French copy-write rules.

Now I mentioned above there is another one know in a private collection, I have talked to the owner and they would prefer to remain anonymous however said it would be fine to post this information. This was purchased at a flea market about 30 years ago for a typical used micrometer flea market price. Most likely the dealer, and if it is who we think it was I knew him, that had it who specialized in selling tools did not know of it's significance... he sold it like it was any other old micrometer. The dealer also would have found it in the US, most likely in a box lot of normal stuff. Now for the best part....... the buyer was a High School age kid who was interested in machine shop stuff and had seen a Palmer micrometer in the book "Shop Theory" put out by the Henry Ford Trade School...... and he had his parents drive him to the flea market....... I think this is fantastic..... it shows there is a good reason to look at old books and kids to sometime soak up what they see!!!!!

I have not seen this with my own eyes... yet. I am told it looks to be steel, the pits we see are not nearly as bad as they look. I touched up these photos, they had been taken under a lamp, they were pretty reflective and the mic looked brass. I am posting them so you can study some of the filing marks, etc...... also note the stamps appear to much deeper...... might this mean this batch was stamped by a different workman with a heavier hand..... or maybe he just grabbed a bigger hammer off his bench?.... I would think if I was making these I might do each operation so I would line them up and stamp the all at once...... from what I see I might think these are from a different batch.





So cool, thanks for sharing Rivett!

You left out one key detail in your story:

How exactly did you come across this rare item??!!
I'll tell how I got this later....... but for now we have a little more info... and what could be called a missed opportunity.

It seems Palmer was at or at least his work was exhibited at he Great Exhibition or 1851 in the famed Crystal Palace in London. BTW Brown and Sharpe did NOT attend this show... see what they missed? The Elliot mics look a lot like the Palmer's.... did this inspire them too????????

And it looks like he shop did even more types of work.... wire? welding? in addition to gauging.

From Google books..... by way of HD. Thanks

Official descriptive and illustrated catalogue, Volume 3
Great Exhibition, Robert Ellis (F.L.S.), Great Britain. Commissioners for the Exhibition of 1851

042 Palmer, Jean Laurent, 16 Rue Montmorency, Paris—Wire-drawer. Various specimens of drawn wire, welding, and instrument for gauging.
I haven't forgot about Palmer.... it is just taking longer to find new information.... this is a translation from something my friends found and another friend with help from his friends translated.... we wanted to make sure we got it right because it shows that Palmer might have started off as a instrument maker and later became more of a industrial manufacturer..... drawing of wire and tubing is a whole different kind of operation than making maybe rules..... It also seems to fit with him moving to larger quarters especially the last move which would have been outside the old walls to city, even though the walls were gone by then the old area would have been densely developed and one would find more or cheaper space the farther from the center of the city......

Report of the Central Jury Concerning Agricultural and Industrial Products… France, 1849.

Monsieur Jean-Laurent PALMER, rue de Montmorency (Montmorency Street), no. 16, Paris.

Mr. Palmer fabricates (makes) his principal products by means of numerous elaborations that he can make metals undergo by subjecting them to the actions of a “banc à tirer” [this translates to a draw bench]. Objects made of copper, brass, nickel-silver, iron, and steel, delivered to commerce/business by this ingenious maker, can sustain comparison with anything made elsewhere by the same procedures.

The Jury calls particular attention to the new processes discovered by Mr. Palmer for making, with the utmost perfection and precision that leaves nothing to be desired, metal cylinders that are very long, closed at one end, and with a uniform thickness. These new products, made successively by chasing (or embossing) them by means of a balance wheel and the “banc à tirer”, offers to the arts of precision, of mechanics, and the sciences, the means of processes that are extremely valuable.

The jury is pleased to recognize/reward the ingenious zeel and the persistent efforts of Mr. Palmer, by awarding him a silver medal.

Here is the original....

"...The Jury calls particular attention to the new processes discovered by Mr. Palmer for making, with the utmost perfection and precision that leaves nothing to be desired, metal cylinders that are very long, closed at one end, and with a uniform thickness. These new products, made successively by chasing (or embossing) them by means of a balance wheel..."

I think this is a description of deep drawing brass shells using a fly press. This process was required to make ammunition for the first breech-loading guns that used metallic cartridges.

The pinfire cartridge was invented in France in 1828 and was based on a deep drawn brass shell. Like all inventions of use by the military, it spawned rapid development and competition.
Pinfire - Wikipedia, the free encyclopedia

The .22 short rimfire cartridge was an American product, introduced in 1857. But it was just an elongated version of the .22 BB cap, invented in France in 1845.

Larry That is a interesting point.... I will have to look for him in the gun world but I think if this type of work was an important part of his work he would have been given credit for it in the press...... we have about 5 or 6 references to wire drawing so far...... here is what wire drawing might have been like in his time...

A different history of the micrometer!

We had a new lead from the wire drawing that Palmer might be involved with music wire...... and look what we found!!!! This is from FELLOWSHIP of MAKERS and RESEARCHERS of HISTORICAL INSTRUMENTS, Bulletin 56 July 1989 and starting on page 56 is a history of the micrometer with a bunch of other people we have not heard of before... it is long but great reading.

• I f

Here is what it says about Palmer.... looks even more like tool was known in France before Brown and Sharpe saw it....

Let us now consider the final stage of the development of the wire-micrometer in the middle of the 19th century. Here we encounter a name well known to us today : Palmer. Jean Laurent Palmer The French inventor Jean Laurent Palmer had completed his micrometer in 1848. At the end of 1849 during a session of the French"Societe d'Encouragement a 1'Industrie Nationale" it was describedunder the name of "calibre a vernier circulate". We find this description in the "Bulletin" of this society, from which we have also taken our figure 6 [n. page] (18).18. "Bulletin de la Societe d'Encouragement a 1'Industrie Nationale",1850, p. 30.
Page 69

The author explains that Palmer's device is built like a screw clamp. A micrometer screw C is added, its screw thread constructed so that each turn corresponds to exactly 1 mm. On the cylinder 6, furnished with a mm-graduation, there is a movable slot (d), the slanted front side of which is subdivided into 1/20 mm. Although our modern micrometers have finer subvdivisions, I need give no furtherinstructions: we all know how to use a "Palmer". I will only draw your attention to an inaccuracy in the description of 1849. The author describes the slanted edge of the slot as a Nonius (Vernier circulaire). That is not quite exact, since a true Nonius, whether circular orlinear, is based on a different principle: a principle we all know from our slide gauge.

It cannot, of course, have been by pure chance that the Palmer micrometer was invented in the native country of the metric system. Let us have a quick look at the chain of components that may have influenced Palmer's inventor's spirit during the advent of industrial production, in the first half of the 19th century, the old manufacturing techniques, depending on places and people, were abandoned. Mass production presupposed among other things the interchangeability of certain technical elements. Therefore it required standardisation. But standardisation is possible only in a situation where all involved use the same measuring system. In France at that time this was already the case. All craftsmen had to be able to adhere to the standard norms, i.e. to use a measuring device valid for all of them. Palmer's micrometer is by far the simplest of all the measuring devices described. Since it was born a child of the metric system, it turned out to be a practical solution for ordering, producing and controlling wires that matched the common standards of all the manufacturers and customers of one country - and later of the majority of a_U_ countries. But Palmer's solution had the added advantage of being capable of delivering scientific data that could be used immediately for calculation: with the help of Euler's formula the length and diameter of the strings may then be expressed in the same unit of measurement. (This was not the case with Streicher 1848).

Page 70
The prophetic words of the author, written in 1849, turnedout to be true: "Sa forme permet de faire un petit outil de poche, sonprix est a la portee de toutes les bourses, sa precision ne laisse rien adesirer, et il est probable, par consequent, qu'U sera bientotgeneralement employe". [Its shape allows it to be carried in a smallpocket, its price makes it available for all, its precision satisfies ourdemand and it is therefore probable that it will soon be in use everywhere.] (19)The success of the French invention did in fact follow the same path as the metric system itself, a path that led around the world
It’s interesting that although Palmer was originally catering for measurers of wire and thin sheet material, he made his micrometers with a relatively wide range and used a relatively coarse pitch.

Today I came across what I thought was a simple and most ingenious instrument for measuring wire diameter, in The Engineer magazine, 1858. Foolishly, I failed to copy the article, so I’ll have to try and describe it.

Imagine a protractor, with a pin going through the centre. Attached to the pin on the front is a finger pointing to graduations on the ‘protractor’. Also attached to the pin, but on the other side of the 'protractor' is another finger. On the outer end of this finger is a cylindrical pin. There’s a small gap between this pin and the periphery of the ‘protractor’.

Now instead of the protractor being circular, it’s machined to a spiral form. In other words, the radius increases with the angle. So, as you rotate the arm, the gap under the pin gets smaller. Instead of graduating the 'protractor' in degrees, use parts of an inch or millimetre. Just shove the wire in the gap, and read off the thickness.

Not versatile, but quick and easy to use on wire.

Hope that’s reasonably clear.
It is interesting to note that the Palmer at the Smithsonian is 20 MM and the other two are 25 MM..... so he was thinking about more than wire.

The gauge you describe is similar to a patented wire gauge in my collection, I think it dates from the late 1860's.... someday I will post it as a separate thread.

BTW...... we are trying to track down a 1850 French article that sounds like it might contain an interview with M. Palmer!!!! This is the sort of thing I have been looking for..... and we found another drawing of the square frame version from the 1880s... it differs from the patent drawing.
Well, my books arrived. Among the 19th century French worker's autobiographies is one fellow who started his apprenticeship as a metal turner in the mid 1850s. He describes in excruciating detail every other job he ever performed, but says nothing about the tools and equipment of the machine shop. :rolleyes5:

I would guess, based on the timeline of machinery development and Monsieur Dumay having been employed as a machinist in cities throughout France, that most of the machining processes we are familiar with were available in the mid-19th century.

As much as I would have liked to see some blacksmiths involved in the production of the first micrometers, it seems unlikely that much forging was involved in their manufacture. (I still like the idea of starting with a 'keyhole' shaped bar, especially if they made hundreds or even thousands of them.) I assume that a horizontal mill would be the primary tool for shaping the frame.

I can't comment on the boring and threading of the barrel. My head hurts if I think on it too hard.