I think AlexP is on to something. Reading the Wikipedia entry on New Latin,
an example of the transition is Newton's writing career, which began in New Latin and ended in English (e.g. Opticks, 1704). A much earlier example is Galileo c. 1600, some of whose scientific writings were in Latin, some in Italian, the latter to reach a wider audience.
The use started declining, in favor of national languages, right at the time “real science” was being invented.
What if the opposite had occured? Once science started getting momentum, people complained about the use of myriad languages to keep up with findings. Furthermore, the need was seen for describing apparatus and procedures precicely so it can be understood for both criticism and repitition by others.
Early examples of poetic phrases, metaphorical expressions, and analogies written by this in other cultures took months to straighten out in correspondence with people using different languages, and the resulting paper trail was a bigger publication than the original paper!
In a move that was similar to computer languages of the 20th century in our timeline, they decided to not only extend acedemic Latin to handle all the new stuff succinctly, but reworked it to allow exact meanings to be agreed upon by all. It worked well for the purpose, and will increasing “new things” arising, developed a framework for extension that kept the precision in contrast to natural language evolution which haphazardly repurposes or changes old words.
Thinking about computer languages of today, and applying that to the need for documenting apparatus and procedures, I imagine a system for exactly specifying antecedents in a succinct way, where each thing refers back to a previous usage or detailed description. We can do this in an ad-hic way with labels: “add the contents of beaker A to beaker B” but this could be a specific language feature, like pronouns, with grammar centered around it.
Second, attributes and descriptions can be both succinct and grammatically encapsulated. For the succinctness consider how I use variables in computer algorithms: A.contents or a notation for how much to take from beaker A. For encapsulated, I mean that phrases expanding on something will be explicitly grouped rather than just running the phrases together. “I met a man with a wooden leg named Smith.” explicitly grouped, “I met (a man with a wooden leg) named Smith.” But add in the advanced antecedent/reference system and you can break out the descriptions and put them first, making the final sentence clear.
Perhaps, although inspired by Latin, they will be sick of all the parts of speech, especially when needing to decline not only the new things being added but encapsulated phrases. In the example above, the whole phrase acts as a noun and we know it’s the direct object due to word order, not by changing the ending—something hard to do on a phrase.
Latin had different groups of words, each of which declined in a different way, with overlapping spellings. So if you keep the idea of part of speech markers, use a regular set of suffixes on all nouns, pronoun/backrefs, and encapsulated phrases. “I met (man with a wooden leg)-acc named Smith-acc” where I’ve marked nouns as accusative.
The real thing would be nicer, but I like the idea of a mark separating the word proper (which does not change) from its marker (which is universal). In the English example the pronoun I is always a subject (nominative case), but in Latin you would generally not have structured it that way, but instead the verb conjugation would indicate “I” as well as “past tense”. At the very least, making the different person, tense, number etc. orthogonal and regular would be a thing to do.
So the English “I met” would be the generic verb “meet” with indications for first person, singular, past, perfective, indicative.
Now this might get simplified as people working on it will come from languages that don’t have some of those things and don’t see the fuss. The constructed language should be designed so it can be used properly by these various members, so some simplification of conjugation is needed.
Will they ditch the attachment of “person” to the verb as a conjugation? If some of the comittee members have languages that do so (as does English) they will point out the benifits of refactoring and how Latin can still have subject nouns too so make it uniform. The killer will be in unifying it with the flexible antecedent/reference system, so I think the subject will be a general-purpose slot for a noun, and possibly can simply be omitted for a default (as we omit “I” sometimes).
They might be less averse to introducing new letters or other special marks compared with today. So the declinations and conjugations may use newly invented symbols, or special separators may be invented to go between the main word and the modifiers.
Another thing to bring up is the idea of namespaces and scopes. If you look at some function available in CPAN, it can be uniquely identified by its quallified package name. The innermost name by itself is not unique, but many authors combine their code on CPAN and everything has a unique fully-quallified name. This is how distinct names with exact unchanging meanings can be managed.
With conjugation/declining handled as a suffix rather than altering the main word, those words are apparent to be looked up as-shown, and you can make up new words without conflicting with all the declined variations or making sure your new one has all the needed variations. So you make up words with a couple syllables in some nice organization, but they also have “sir names” that make them truely unique. An import mechanism lets you skip or abbreviate the sirnames within a publication.
To summarize, a lot of what we’ve learned from constructing high-level computer languages over the last 60 years can be applied to designing a language for describing observations, procedures, and apparatus. A lot of the features cary over: exact meanings, extensibility, compactness.
I suggest starting with Latin due to plausible history. But it will end up looking about as much like Latin as C++ 14 resembles CPL.