Military equipment has always had a designation of some sort. i.e., fighter, scout, destroyer, frigate, etc. The Tripod ‘Mk.’ designations appear to be based on the order of their appearance, not their hull classification and/or fire power. Looking at the descriptions of the various Martian Machines and taking page from the navy, as they are basically landships, I came up with these hull classifications;

Mk.I “Locust”: Destroyer
Mk.II “Scarab”: Cruiser
Mk.III “Squid”: Scout
Mk.IV “Cuttlefish”: Battleship

This would open the possibilities of subvariants, like a Mk. Ia might be a Fast Destroyer or a Mk. IIIb a Heavy Scout.

Thoughts, Comments?