Happy Fourth! 
 Seems a stroke of genius to fit in a 15 x 15 grid 
THOMASJEFFERSON across the middle and then cross that  with 
THEDECLARATION and 
OFINDEPENDENCE. (Note the interesting grid structure.) 

 Working 
JOHN and 
ADAMS into the grid is a bonus. 

 There even was a riddle:  
What can’t be parted after it’s departed?   HAIR 

 As this is a Monday, it was also made easy to solve.
The only stain was OST, but even there the clue was good, “East, to Ernst.” [I would have gone with “Bone, comb. Form.”]
RATING:   
 
 
 Three grins = Excellent: Loved it; Two grins = Good: Enjoyed it; One grin = Satisfactory: A bit bland for my taste; One teardrop = Unsatisfying: No fun