polymathy

Albite is NaAlSi3O8.

K-feldspar is KAlSi3O8.

Together, they form a partial solid solution. They tend to swap out out K (very large) for Na (much smaller), which is only enthalpically favored at certain temperatures. At many temperatures, it is not, and the liquid/melt is more favored. The diagram is somewhat complicated.

In contrast, albite/anorthite swaps Na+Si with Ca+Al elements in the framework. This sounds harder but actually results in a more cromulent enthalpy under more circumstances. So you can get a solid solution, albeit often a more zoned one than olivine, where Mg and Fe swap in and out easily.

K-feldspar = KAlSi3O8

Albite = NaAlSi3O8

Anorthite = CaAl2Si2O8

Forsterite = Mg2SiO4

Fayalite = Fe2SiO4

Types of phase diagrams:

Binary systems with a eutectic (anorthite + diopside)

Binary systems with a peritectic: forsterite + enstatite + silica

Binary systems with a thermal barrier: nepheline + albite + silica

Binary systems with a solid solution: plagioclase (ranges from sodium-rich (albite) to calcium-rich (anorthite)), olivine (ranges from magnesium-rich (forsterite) to iron-rich (fayalite))

Binary system with partial solid solution: (albite + K-feldspar orthoclase)

Ternary systems: cotectics, 3-dimensional diagrams,

Mostly rocks and their melts have the same composition. Sometimes the silica separates out, though. This is incongruent melting.

An An-Di melt will remain a melt until it hits the liquidus curve. Then a small amount of either anorthite or diopside will crystalize, which will move the composition along the x-axis. Then crystallization will stop, until and unless the temp drops further.

Down we go along the liquidus curve. Once we hit the eutectic, a small drop in temperature will result in all the other solid crystallizing.

In systems like these, the fractional crystallization path is the same as the equilibrium crystallization path, because the crystals don't react with the melt.

A simple rule for the melting of most substances is that the temperature at which the solid will melt is highest when the melt has the same composition as the solid.

Why? Gibbs free energy.

Enthalpy is the measure of heat that is tied up in chemical bonds. Reactions release or consume heat based on bond strengths.

Entropy is a measure of randomness, which, in this particular case, is a function of how tightly bonded atoms are in the structure.

A pure substance (such as anorthite or diopside) has a favored state that results in a crystal structure. Each crystal structure is different (how different depends). If you have a pure substance in a crystal form, that's a nice, tightly locked, thermodynamically favored structure. It takes a lot of energy to break it up = higher melting temperature.

If you mix it up, the crystal structure is less orderly, less favored, it takes less energy to break it up (lower melting point).

Anorthite favors precisely ordered mix of Al and Si tetrahedra https://virtual-museum.soils.wisc.edu/display/anorthite/
Diopside is chains of SiO₄ tetrahedra with Ca²⁺ and Mg²⁺ in specific sites https://chem.beloit.edu/edetc/pmks/pages/diopside.html

Anorthite is a calcium-rich plagioclase
Diopside is a pyroxene

Anorthite and diopside are not equally competitive with the liquid at the same T, unless you are exactly at the eutectic.

Why?

The melt composition is closer (in a thermodynamic sense) to one structure than the other
That structure can lower its free energy faster relative to the liquid

So at a given bulk composition:

One structure fits the available local chemistry better
The other would require larger rearrangements / worse site fits

To form Anorthite:
You must extract Al + appropriate Ca + Si and build an ordered framework
If the melt is Mg-rich (Di-lean), that’s relatively easy

To form Diopside:
You need Mg in the right proportion and chain structure
If Al is abundant, that structure is less favored

Only the eutectic equally thermodynamically favors both

1a. Gabbro from the Medford dike
coarse-grained, basaltic/mafic, forms underground (intrusive)
it's a dike, meaning it seeped up through a fissure in the country rock
Medford dike (TRm) formed in the Triassic, 238 Ma, just after first dinosaurs
Country rock: Zlwg southern border & Zpt slightly north

Unit symbols for Neoproterozoic rocks use the “Z” designation adopted by the U.S. Geological Survey

2. Abandoned quarry in the gabbro Medford Dike.
Gabbro was quarried beginning in the early 1800’s for building stone, monuments, and hitching posts that can still be found in downtown Medford.

The quarry wall shows deep weathering

3. flat-topped ledge of gabbro
glacial erosion
glacial grooves in good light

4. Cross from the Dike to the Lynn Volcanic Complex (proterozoic)
felsite
lighter-colored

5. smaller dolerite dike
dolerite mafic, like gabbro compositionally, but larger grains (medium sized)
Diabase dikes and sills are typically shallow intrusive bodies

On Map 1A and throughout the Fells, dolerite dikes are common, and we know they have several different ages by the way they crosscut each other.

In the beginning was the Big Bang.

Fast forward, and there's a planet Earth, oceans, and continents. The most complex life forms were the fishes.

390 million years ago (Ma), the fishes learned to live on land. Their fins evolved into legs, which led to paleontologists calling them tetrapods. But they still had to return to the sea to lay their eggs. They were thus amphibians.

Around 325 million years ago, we were smack dab in the middle of the Carboniferous period. This means there were lots of trees in the tropics. These trees repeatedly got buried in swamps due to cyclical rising and falling of sea levels. These trees were buried in such vast amounts in the latter half of the Carboniferous that they are responsible for a lot of our coal resources today, especially in western Europe and the eastern US.

There were warm, wet forests around the tropics and ice caps around the poles. It was an ice age: the ice spread remarkably far away from the poles. This means there were strong temperature gradients between the poles and the equator. One illustration of this is gradient is that trees near the poles have very distinct growth rings, because those reflect significant seasonal temperature differences. In contrast, trees near the equator don't show marked rings, because temperatures were more stable throughout the year.

Around 325 million years ago, the polar ice cap melted, causing rising sea levels.

This coincided with one amphibian lineage splitting into two lineages, one that would become reptiles and one that would become mammals.

2 large landmasses: Gondwana at the South Pole, Laurasia at the equator. Eventually they collide and form Pangaea. That collision forms the Appalachians.

The reason there's an ice cap is that the giant trees are pulling carbon dioxide out of the atmosphere and getting buried. Less carbon dioxide in the atmosphere means lower temperatures (no greenhouse effect). Lower temperatures means growing polar ice. Growing polar ice means lower sea levels. Lower sea levels mean less flooding. Less flooding means more trees. More trees mean warmer temperatures (apparently). Warmer temperatures means melting ice, flooding, and tree burial.

Moreover, when bacteria consume organic material and cause it to decompose, they consume oxygen. This means less oxygen in the atmosphere. So burying the trees and keeping them from decomposing not only meant less carbon in the atmosphere, it meant more oxygen.

More oxygen in the atmosphere means arthropods, like insects, can grow much larger. Dragonflies could achieve wingspans of up to .75m/2.5 feet. Millipedes got up to 2.4m/8 feet long.

All of these patterns get reversed during the Permian, when the ice age ends.

While this is going on (ca 325 Ma), some amphibious tetrapods learn to insulate their eggs with fluid. This means the embryos can grow in the egg on land, without having to get their water from the ocean. This means the tetrapods can live full-time on land, i.e. not be amphibious. These creatures are called amniotes, because they lay amniotic eggs (eggs with amniotic fluid).

These amniotes are the ancestors of reptiles and mammals, both of which are full-time land dwellers.

In the middle of the Carboniferous period, the weather changed. It switched from the Mississipian period to the Pennsylvanian period*.

These amniotes then split into the future reptile and mammal lines, which are distinguished by the number of holes behind the eye sockets for anchoring the jaw muscles. Reptiles have 2 holes; they are diapsids.** Mammals have 1 hole; they are synapsids.

If I understand correctly, synapsids split off first and evolved one hole, then diapsids evolved two holes.

Then around 307-310 Ma, the Carboniferous Rainforest Collapse happened, inaugurating the Permian Period. The ice caps melted, coal swamps replaced by seasonal, semi-arid drylands, and some deserts arise in Pangaea. Trees have to be better adapted to drier conditions. Some extinctions, especially in the plants (one of only 2 extinctions in the plant record).

Amniotic eggs are now a superpower that allow you to roam more and live in drier conditions. This helps explain why in the Carboniferous, amphibians were large and numerous, but now they are small. The larger animals became reptiles and mammals.

Now we're in the Permian. We start to get more mammal-like animals. They become increasingly warm-blooded, meaning they generate more and more of their heat inside their body, instead of absorbing it from the air around them. They start to develop hair. The hair starts as only a few hairs for sensory purposes, like a cat's whiskers, but eventually starts to cover the whole body. If you're generating your heat internally (i.e. are warm-blooded), it's efficient to have an insulation layer. This is why most mammals (warm-blooded) have body hair, birds (warm-blooded) have feathers, and reptiles and amphibians (cold-blooded) don't have this insulation layer.

We're not sure *why* warm-bloodedness evolved, but being warm-blooded means you can run faster and farther without having to rest and soak up more sun.

These animals also started to change their locomotion and posture. Instead of crooked limbs that sprawl out to the side, like lizards and crocodiles, their legs become more and more straight and more and more directly underneath the body. Their limb joints can also move in more directions now, which means they can run, dig, and climb.

All these new traits combine to make them better hunters and better able to explore new terrain.

These increasingly mammal-like animals that lived during the Permian are called therapsids.

Then volcanoes known as the Siberian traps were so active that we had the famous Permian extinction event. Therapsids got a lot smaller, and that helped them survive. They could burrow into smaller spaces to find shelter, and they needed less food and could eat smaller food. Furthermore, they evolved to mature faster, producing lots of offspring and dying quickly. That numbers game helped the species survive very difficult conditions.

After the end of the Permian period, we leave the Paleozoic Era and enter the Mesozoic Era. That is the age of dinosaurs.

Because dinosaurs were becoming very big and tended to prey on small mammal-like creatures, these small mammal-like creatures started to become nocturnal. They lost color vision, which they no longer needed. Only a few of us, mostly primates, have since gotten it back.

Full on warm-bloodedness develops in the Triassic period (the first period of the Mesozoic Era). Warm-bloodedness and cold-bloodedness are two ends of a continuum, and the continuum is just: "How much of your body heat do you generate internally vs. depend on the external environment for?"

Warm-blooded animals can run faster and farther with their higher metabolism, but that higher metabolism consumes more calories at rest, and need more oxygen.

Around this time, the increasing shift of legs under the body and other skeletal changes means these mammal-like creatures stop undulating when they move. They now move straighter and faster. This change allows them to stop compressing one lung with each side-to-side undulation. Not compressing their lungs helps increase their stamina, because they get more oxygen when they move.

Then things get really interesting with the jaw. The jaws of amphibians, reptiles, and mammals superficially look similar, but if you start staring at the bones underneath the flesh, you see very important structural differences.

The ancestors and relatives of mammals have lower jaws made of many bones. We only have one: the mandible. Several of the other bones fused together in mammals. As the jaw bones were fusing together in early mammals, they did so in a way that allowed stronger jaw muscles to form at the new joint. This allowed stronger biting, which allowed mammals to expand their range of food.

The change also came in concert with new kinds of teeth, and tooth alignment between the upper and lower jaws. Instead of just some pointy teeth that could puncture an animal, jaws that could snap shut, and the ability to swallow prey whole, mammalian bone-muscle-teeth changes in the jaw led to them developing the ability to chew their food.



, or else became very small and moved back into the ear, where, as the malleus, incus and stapes, they help transmit sound. You may have learned about these ear bones in school under the names hammer, anvil and stirrup.

The interesting thing is

ontogeny recapitulates phylogeny
teeth can chew food instead of swallowing it whole


oxygen
greenhouse warming
tree rings

* N. Am. terminology; elsewhere Lower Carboniferous and Upper Carboniferous.

** They are called diapsids for cladistic reasons even if individual species later lost a hole.

***This ends up being so important that for a long time "mammal" was defined as "all animals that descend from this ancestor animal that developed this new joint in the jaw."

Not what you think of when you think of a mammal! But the one that makes the most sense in cladistic terms, apparently.

Recently, apparently paleontologists have decided to define mammal as "descendants from the common ancestor of all modern living animals." This means animals that were cousins but came from a clade that didn't leave any descendants are excluded, even if they did all the things we think of as mammals doing: looking, behaving, growing, metabolizing, feeding, nursing, and grooming their hair just like mammals.

Reinhold Koser drew our attention to the report of the Danish ambassador, Johnn, by saying that it resembled the 1731 anonymous pamphlet so closely that it was an important clue to the origin.

They are the only two accounts I'm aware of that have Katte invoking the King in his last words. They're also the only two that have him saying "If I had ten lives" instead of "a thousand." There are numerous other details that we find nowhere else, such as the coffin being made of four planks. (In the actual pictures I've seen of it, it appears to have five: bottom, two sides, and a V-shaped top. Not counting, of course, the two short sides.)

Since the 1731 pamphlet contains the letters from Katte to his family and the King, the Danish ambassador most likely had someone with access to the Prussian archives in their pay.

The date and time of the execution being wrong are attributed by Koser to printer's errors. In a text that includes a hand-foot (Hand-Fuß) instead of a hand-kiss (Hand-Kuß), this seems likely.

It's worth knowing that both Wilhelmine, in her memoirs, and Friedrich, in Mitchell's memoirs, credited the Danish envoy Løvenørn, Johnn's colleague, with giving Katte warning of his impending arrest, warning that Katte did not act on in time.

Now, if Wikipedia is to be trusted, Løvenørn was recalled to Denmark in October, so he was not in Berlin when the execution took place, and was probably not the one responsible for leaking the letters in the Cologne pamphlet. This would imply that both envoys, Johnn and Løvenørn, were highly sympathetic to Katte, and perhaps acted out of personal sympathy and not only their diplomatic mandate to advance the cause of Denmark at Friedrich Wilhelm's court.

Koser also tells us that the order to arrest Katte arrived on the evening of August 15, but was not delivered by the postmaster to Natzmer until the morning of August 16, despite the fact that it was sent by urgent post. We are speculating that the delay might have been deliberate and the postmaster might have been in the pay of one of the envoys, perhaps Danish or English.

Koser was also the one who brought to our attention the fact that there were two Münchow letters that contained similar but contradictory information, and that Münchow's age is a thorny topic.

In the 1886 first edition of his biography of Friedrich as crown prince, Koser quotes the contradictions, then says, "One won't want to trust this witness anymore." In his 1901 second edition, he deletes that sentence. Hoffbauer, in 1905, takes this to mean that Koser changed his mind and considered Münchow a reliable witness as far as the layout of Küstrin was concerned. Since he also, in the second edition, concludes even more strongly that Münchow is probably wrong about his age in every statement he made about it, and that he was thus probably only four at the time of execution, I have to wonder how reliable Koser really thought Münchow was.

What's interesting to me is that both Johnn and the pamphlet have Friedrich being informed of the impending execution at 5 am. This matches the report given by Lepel to Friedrich Wilhelm on November 8, which was probably delivered to Berlin by express post on November 9. Johnn's letter is dated November 11. This means he has accurate information that couldn't have been witnessed by any of the 150 soldiers that were standing outside during the execution.

I think it's therefore likely that Johnn had access to the letter in the archives a scarce day or two after it was delivered.

What's interesting is that Lepel, in his November 8 account, which is likely doctored to at least some extent to keep the King happy, reports a captain and a colonel reporting the news to Friedrich, but not either himself or Münchow Sr. The 1731 pamphlet has "two captains," which is extremely close. Münchow Jr. says his father was present, which is slightly more reliable than Wilhelmine's account that Münchow and Lepel were present. Catt and Voltaire both agree there were two officers delivering the news, and some grenadiers who were responsible for dragging Fritz to the window.

I still consider it possible that Lepel and Münchow were both present in the room when the news was delivered.

Of interest probably only to me, but this came up while doing fic research.

When Fritz made his escape attempt and was trying to hide the fact that he had been having dealings with the English, he confessed "that he was planning to flee to Strasbourg (where he seemed to have his eyes on a stay on the Alsatian estate of the French envoy, comte Rothenbourg)." Quote MacDonogh. I've also seen other sources state that Katte had suggested Rothenburg's estate as a safe haven, and that this was one of the pieces of evidence used to convict of Katte of being up to his ears in this plot and helping advance it further than it would have without him.

Being me, I've been wanting and wanting to track down this estate, just like I did with Peter Keith's.

Well, I finally turned it up, and one reason it took so long is that it's not nearly as close to Strasbourg as that sentence had led me to believe. Comte Rothenburg/Rottembourg (however you want to spell his name) was feudal lord of the seigneury of Masevaux, 120 km south and east of Strasbourg, and about 40 km from the modern French border.

It also gets a bit more complicated than this. Rothenburg was descended from Conrad de Rosen, who was a field marshal and a member of a prominent family. Conrad bought this property from the Fuggers (famous German banking family), then sold it in 1684 to his son-in-law, who was our Comte Rothenburg's father.

Conrad meanwhile hung on to the Dettwiller, Herrenstein, and Bollwiller estates, though Bollwiller had been pawned to the Fuggers by his father-in-law, and Conrad had to pay that debt. These estates were passed down the Rosen line.

Comte Rothemburg, during his lifetime, acquired the nearby estate of Rougemont. On his death, his estates, Masevaux and Rougemont, went to his sister.

Now, I had thought both his sisters were childless, but it turns out not, because sister had a daughter. Daughter inherited the Rothenburg estates, and married the Rosen heir of Conrad's estates. Thus the Rosen family became one of the largest landowners in Alsace.

Here are Bollwiller, Masevaux, and Rougemont situated on the map in relation to each other and Strasbourg.



Parts of the original manor house in Masevaux remain standing and are protected as a historic monument.

I also found out that our Comte Rothenbourg's library was assessed after his death, and thus I know that it contained 156 books, most of which were in French, and, amazingly, I know the distribution of these books as well:

Religion: 5%
Law: 8%
History: 22%
Belles-lettres: 43%
Sciences & arts: 13%
Various: 9%

Now, this is only the books of value, because smaller books were not recorded, but even so, I have to say...this is not going to be enough for Fritz in my AU. That library's going to have to be expanded once he decides he's moving in permanently. :P

Otto Gustav von Lepel was the commandant and governor of the fortress at Küstrin in 1730. He was the one charged by Friedrich Wilhelm with Friedrich's imprisonment and Katte's execution.

On November 6, he wrote the following note to Friedrich Wilhelm, stating that the execution had been carried out. This report is given by Hoffbauer on page 42 of his 1905 monograph Die Kattetragödie in Cüstrin und ihre Stätte. Translation mine.

( Text )

( Translation )

Hoffbauer reports that on November 7, Friedrich Wilhelm wrote a letter to Lepel demanding more detail. Lepel then replied on November 8 with the following more detailed account, given by Hoffbauer on pages 45-46. Translation mine.

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( Translation )