Decimal time notation

For some time I have looked for examples of how decimal time was used in France, so that I can represent it accurately in my scripts.  Most of them are written out in full, as in "five hours and fifty minutes decimal".   In both French and English of the period, it was customary to write a small "h", "m" and "s" after the hours, minutes and seconds, respectively, and even today it is common in French to put an "h" between the hour and minute, instead of a colon.  It therefore seemed likely to me that they would have written decimal times in a similar way, although they would have to distinguishable from standard times.

I have been trying to read Essai sur l'unification internationale de l'heure (Essay on the international unification of the hour) by Joseph Charles François de Rey-Pailhade, published in 1893.  Mostly it is about his proposal to use the centiday and the milliday, which he called cé and decicé, but he also writes about related subjects, including decimal time from a century previous, and includes examples such as:
3 heures 93 minutes (système décimal) 3hd 93md
It's a bit awkward to use double letters for each unit, but it seems likely to be correct, so I going to use this notation from now on.

Decadi 30 Nivôse an CCXVIII à 5hd 77md t.m.P.
MJD 55215.570

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