This one pretty much was over right when it began. Just to be warned, I spoil what is essentially the only puzzle in the game.
From the Museum of Computer Adventure Games.
It turns out getting past the hydra was the only thing to pose any difficulty. I found out the game has a HELP command which when applied in the hydra room gives this cryptic message: “CIGAR? CIGARETTE? TIPPARILLO?”
There’s a nearby cigarette lighter, and I thought — no, it can’t be —
>BURN HYDRA
THE HYDRA CRUMBLES TO THE GROUND DEAD.
Alas, the humble lighter was invented too late for Hercules.
Past the hydra there is a “Mac’s Earthdigger Body Shop” which has the “gonkulator” which you use to fix your ship. No treasures are necessary at all — you can just pick it up, drop in the ship, type FIX GONKULATOR, and get game over.
I hoped, perhaps, there would be challenge then in collecting all the treasures. The “secret passage” on the map has some randomization but other than that all the treasures are in the open.
I have marked on the map all the unnecessary parts. (Click for a full sized version.)
The “shiny sword”, “magic wand”, and “keys” are all useless. The “treasure room” is a joke. I don’t mean that flippantly. It is an actual joke room:
If you go back to the Scott Adams interview I linked to when I wrote about Adventureland, he mentions when he hit the limits of the TRS-80 he knew he was done. The same thing must have happened here; I suspect the author had grand ambitions but ran out of space. Journey to the Center of the Earth Adventure gave me a greater appreciation for Scott Adams’s choice of minimalism in text allowing for greater complexity in game-world.
I have played a later Greg Hassett game (Devil’s Palace) which I enjoyed, so I know at least things are going to get better.
Renga in Blue 
It was sort of a shock to see this pop up in the Planet IF feed right after the introduction post. I guess too easy is better than too hard, right? Right?
This was definitely my shortest yet. The only reason it went past the IF-comp-2-hour mark is I was trying to make a careful map for documentation purposes.
I get irritated by the reverse chronological effect when the two posts in a row at Planet-IF happens. (If you use the links at All the Adventures above the posts end up in the correct order.)