It's a Seymour Ironclad scythe snath. The H is just a foundry mark from the contractor that did the malleable iron castings for them. The blade is a bush blade, and the "extra" holes (as mentioned) were for altering the hang (pivot) of the blade. The shape of that squat tang leads me to hazard a guess that it may be an Emerson & Stevens, though Rixford is another likely candidate. There's typically a stamp on the tang on the side facing the hardware, so you usually have to take the blade off to see the marking (although some companies, like True Temper, often marked the underside of the tang, instead.)
The nibs (side handles) use a left-handed thread, so turn RIGHT to loosen. When assembled there should be no wiggling of the hardware or else you'll quickly damage or break the snath even if the wood isn't compromised. The blade will need grinding and honing before it can be put to work, and--depending on how you intend to use it--possibly the shank of the tang heated and bent to a more ideal angle for your uses than it lays as-is. Any slack in the fit of the parts will need to be taken up, and all wooden AND iron components should be inspected for cracks, splits, and any other possible damages. The grips of the nibs are often severely weakened from age, but sometimes you get lucky and they aren't cracked.
