Hull Constitution Model Rigging Question

I think I agree with George.  The big block hanging level with the foretop certainly appears to be the upper block of the topsail halyard.  (The line from which it's hanging is usually called the tie, or tye; the somewhat lighter line that runs through the sheaves of it is called the halyard, or halliard.  The whole assembly is often referred to casually as the halyard.)  The one in the other two shots certainly appears to be the aftermost of the two breast backstays on the starboard side.  

I may be wrong about that, though.  Sorting out the leads of lines in photos is notoriously difficult.  That particular model is generally regarded as an encyclopedia of 1814-vintage American rigging practice; the guy (or guys) who rigged it clearly knew exactly what he was doing (or what they were doing).  (The same can't be said about the hull and deck details, which are downright crude by comparison - but of enormous interest nonetheless.)  It's easy to study the rigging of a model like that in person; you can walk around it, look at it from different angles, and follow each line from end to end.  But trying to figure it out on the basis of photos is a great way to go crosseyed.  The Hull model makes a wonderful reference for modelers trying to depict the Constitution in her War of 1812 configuration. Personally, though, I don't think I'd want to try it unless I lived within driving distance of Salem, and could go look at the model whenever I ran up against a question.

I’m not an expert on the rigging of American ships, being from the UK,  but the differences with English practice should not be that great. There are two lines on the pictures you show. The block in your first picture relates I think to the topsail yard tye.

 Blocks are stropped to the Topsail yard and Cross trees thro' which the tyes run port and starboard.

 The tye starts at the mast head above the cross trees, runs down between the centre of the crosstrees, reeves thro’ the yard tye blocks, up thro' the upper tye blocks and continues down on a long pendant with a double block seized in it end.

 The Topsail Tye halliard starts at the channel to a block seized to an eyebolt.The line runs up thro' the pendant block then run down thro’ the channel block back up thro’the pendant block and down to the deck and belays on a kevel inside the bulwark.

This is the tackle shown in your second picture.

The Channel tackle shown in your third picture relates I think to a Topmast breast backstay which in the pictures appears to pass close by the  topsail tye tackle hence possibly the confusion, but the two lines are not associated. The breast backstay is part of the Standing rigging, and the topsail tye part of the running rigging.

Hope this helps