@lori - excellent site.
Re Hudson Bay Bread. Looks good, but I would suggest that the history is probably false. I attended the UK army outward bound school in 1961, and the recommended high energy food was "Edmund Hillary's favourite - Kendal Mint Cake." (This is a sugar/glucose opaque confection flavoured with peppermint.) as an alternative, fruit cake was recommended. Hillary was rumoured to have taken 4 tea chests of Kendal Mint Cake to the Everest expedition and the party complained that there might not be enough! Certainly, I can report that pupils of the Outward Bound School consumed enormous quantities of Kendal Mint Cake and we all placed copious quantities of it in our packs as "emergency rations". Nowadays I prefer home-made fruit cake which contains complex and simple carbs, dried fruit, nuts, and if I made it, a good slug of rum. Makes it moist and delicious. Slather it with butter to up the fat content. I suppose modern energy bars are easier, but much less fun.