Yes Capt. Mark, the narwhal 'red herring'
and it would seem the Scots would naturally have had an affinity for this horn as thier national arms are supported heraldically by flanking unicorns
Carl, Im really glad you posted your bilbo here! It is really a great example, and good to see these Spanish Colonial weapons becoming so well represented here. These were of course military swords, but not really a particular regimental pattern. The dates that are applied to these swords such as '1728' were simply dates referring to regulamentos (if I recall correctly) of the years 1728 and 1768 where military inspections were emplaced to record the state of units and presidios at the time. Swords with these traditionally styled hilts were in use widely and over extremely long periods of time, especially on the frontiers.
Your blade is well placed here as it corresponds nicely to Fernando's cuphilt and is also of the somewhat triangularly elongated form, yet with the typical hexagonal cross section of the later dragoon blades.
The initials N M N on the blade are not for a maker but actually would probably be an acronym for a religious invocation such as those seen on much earlier sword blades, again a tradition long held and carried forward from such sacredotal inscriptions. Examples known from earlier are i.e. N E M, = Nomen Eternis Nomen and N O M , =Nomen Omnipotentis Nomen.
While cuphilts such as Fernando's were apparantly a favored horsemans weapon, the bilbos seem to have been often associated with infantry officers of line regiments in most cases I have seen. There seem to be a number of examples from Cuba and units in the Spanish holdings in Florida and Louisiana.
The differences between rapier and bilbo as seen here are in my view purely semantical, as these are both actually 'arming swords' which reflect earlier styles of rapier in tradional forms.
All the best,
Jim