channels on the bulwarks leave me confounded.

Are you perhaps referring to the deck drainage gaps beneath the bulwarks. On fishing vessels they are known as freeing ports. The clearance of deck retained water has to be very quick if a large quantity is taken on deck and does not escape quickly Causes stability issues when vessels have deep bulwarks capable of holding back huge weight of water if seas are taken aboard.
 
Channels are strips of wood to which the chainplates are attached that hold the shrouds further away from the hull. The bulwarks are the part of the side of the vessel above the level of the deck.

So presumably Kate has her channels mounted on the bulwarks in a way that is peculiar. Given the forces involved it seems strange to mount them higher than the deck
 
Channels are strips of wood to which the chainplates are attached that hold the shrouds further away from the hull. The bulwarks are the part of the side of the vessel above the level of the deck.

So presumably Kate has her channels mounted on the bulwarks in a way that is peculiar. Given the forces involved it seems strange to mount them higher than the deck

...reckon you're right... here you go..

Capture.JPG
 
They were commonly used on sailing ships to extend the shroud base outwards, For the same reason in naval vessels as they often had quite extreme tumblehome, this kept the centre of gravity of the higher decks of cannon towards the centreline, channels on vessels like this were a necessity to put the shrouds outwards
 
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