Several of the other initial caps have a ball flourish too. R in particular appears in 2 different forms. Neat example!

Maybe this is an old cartographic standard to indicate the end of words set at very large sizes –which may appear a bit hard to recognize in maps with lots of information. But this is just a guess, I have no information on it.

I'd definitely be interested in your proposed TypeCon talk.

I am Dutch and in the modern Dutch language there is no such thing as two capital K's. Seeing the structure of the Dutch language I assume that this wasn't the case a few centuries ago. But I am not an expert

I would recommend you to post a threat in the Dutch cartographers group on LinkedIn. Here is certainly someone who can provide you with more insights using the K balls or point you in the right direction.

http://www.linkedin.com/groups/Nederlandse-kartografen-Dutch-cartographe...

I don't think Dutch ever has had distinct forms of K. This could well be embellishment.

On this map you can find examples traditional long vs. short s, but to my surprise, there is at least one occurrence of a long s at the end of a name -- "Bourneus" near the top. I don't think that was usual.

Also, it's a French map but the long s/short s in "Lußon" (above "Rochelle") suspiciously looks like a German eszet. It could be a sign of the times, but of course it also might simply be mapmakers' errors :-)

@Theunis de Jong:
Also, it's a French map but the long s/short s in "Lußon" (above "Rochelle") suspiciously looks like a German eszet.

Nothing suspicious about that at all. That's the normal way doubled s was handled when long s was used, whether one was printing English or Latin. The German eszet today is just a vestige of the fact that German printing retained the long s longer than anyone else's printing, since the long s was part of Fraktur; so Germans were so used to the appearance of a double s that they retained the eszet even when they discarded the long s upon moving to Roman typefaces.

Claſsic!

Thanks, now that makes perfect sense.

Ok, perhaps stupid, largely un-researched question, but if memory serves Peter the Great visited the Netherlands around this time, eventually adopting Cyrillic back home. Could these different forms, which were more than likely just stylistic, have inspired him or others that developed the modern Cyrillic script?

The heavy terminals on the Cyrillic К are a feature of pre-Petrine manuscript styles, so I don't think the forms you show could be considered a source for the conventional distinction between the Cyrillic К and the Latin K.

I have a much later (1864-1950) finnish map with ball-terminals on italic K's, and I have also thought of it as cyrillic influence. Most of the map is actually made during the years of Russian rule. Another feature that seems like cyrillic influence is the barred tops of A's. Both of these appear in italics and backward slants only, but not in all of them. All the all caps words have conventional forms.

This book might be interesting:
http://bit.ly/nr1OJx

It's natural for hand lettering to show deviations from the norm.
These may be haphazard, or evolve into a personal style.
Such styles can become infectious, and at some point a typeface may succumb to the variant, either as default, or in some cases as an optional sort. That was very rare pre-digital, but now, if you're a type designer and can't make up your mind whether your typeface should have a one- or two-storey "a", no worries, just include both, thanks to OpenType stylistic sets.

A different implementation, perhaps in the spirit of the old map: when I upgraded Fontesque with a pesudo random feature, the extra "K" was indeed Cyrillic-style.

As an aside, Archer's employment of balled terminals in C, G and S does not extend to the K.
I suspect there are some lesser-known types available that have balled terminals in the caps, including K.
Anyone?