in the last years of the 16th century , five different Dutch admiralty colleges were established, In 1795, in the Netherlands and Belgium the designation  is Admiralty (admiraliteit) replaced by navy (marine): 
the five admiralty colleges were:
1.Amsterdam
2.Rotterdam
3.Friesland 
4.Zeeland 
5 Hoorn and Enkhuizen
if you read embossing, one can read indeed ADMIRAITEIT and below the letters 
ESL
 
So the conclusion is that the cannon may have belonged to the Dutch Admiralty friesland
ADMIRALITEIT
FRIESLAND
for an early one please see 
http://www.friesscheepvaartmuseum.nl...n/Admiraliteit
best,
Jasper