Yesterday at 3 p.m., P.H. and I climbed into Ocean Voyager's two submersibles, Jules and Jim, for our first dive down to Yamato's wreck. All I brought with me for the trip down to the ocean floor was a towel for warmth, a supply of video recorder beta-tape from the TV Asahi team, and my copy of Yoshida Mitsuru's memoirs of Yamato's last mission.

Unlike the tank-like titanium submersible Nautile that we use on Titanic research and recovery missions, these acrylic-sphered, two-man subs look more like blue and yellow toys from F.A.O. Schwarz than serious ocean exploration vehicles. Despite their cute design, though, they're the best equipment for diving down to a maximum of 1,000 meters (3,300 feet).

Created by Californian Graham Hawkes of Deep Ocean Engineering, each sub is air-conditioned and has two six-axis, remote-controlled, robotic arms capable of doing what human arms can do. The battery-powered vehicles carry 120 hours of oxygen in case of emergency — well above the international emergency standard of 72 hours — and we have individual breathing mouthpieces in case of sphere submersion or electrical fire. Dying of the cold in 48 hours — the greatest risk divers encounter on Nautile — isn't a great concern with these subs because their acrylic spheres allows in heat and don't dive to Nautile's bone-chilling depth of 20,000 feet.

Once our pilots — Sydney Lalleman for Jim and Denis Poullain for Jules — finished their pre-dive checklist, we were ready to roll out on the subs' heavy iron track to the launch point at the stern. Our drop zone was marked by five orange and yellow balloons riding the surface of the sea — held in place by a rope, more than a thousand feet long, that tautly connected them to the ocean floor and the wreck site of Yamato. The ship lies 1,130 feet below the surface on the edge of an ocean cliff, too deep for divers outside the protection of a manned submersible. The rope would be our road map to the bottom — leading us to a landing spot 30 meters south of Yamato's bow — and it would be our highway home at night.

Once we were in the water, Julien Nargeolet — a navy frogman and P.H.'s son — dove under our subs to release the last threads of rope holding us to the surface world. As we began to dive, Julien, swimming around us, was clearly visible, and sun enveloped us, beaming in the colors of the sea and refracted sunlight through our 5.5-inch-thick acrylic spheres.

We dropped — five minutes, ten, fifteen, then twenty. The sunlight above faded — first the brilliant colors and then all color. Finally, even the grays disappeared as we descended through a thousand feet of ocean. Twenty-five minutes from the surface, we arrived on the seabed — a much quicker trip than the two hours it takes to reach Titanic, much farther below at 12,500 feet.

Our lights came on, and we hovered alongside the guide rope. We looked around and couldn't believe our eyes. The site was a landscape of armaments — munitions, cartridges, gun powder everywhere.

If it had been possible for me to step out of Jim at this depth, I would barely have been able to avoid walking on munitions with each and every step. Twenty-five mm cartridge shells were strewn across the sand like pebbles. Large 127 mm cartridge shells and even larger 155 mm cartridge shells were tumbled about like so many rocks and boulders. Cordite powder barrels and large depth-charge canisters added to the madness of the world of Yamato deep beneath the surface of the sea.

And these were not even the munitions of the big guns, Yamato's 460 mm, 18.1 inch cannons — the largest naval guns that were ever made. Their firepower was awesome. Each of Yamato's nine guns could fire a 3,200 lb., armor-piercing shell a range of 30 miles.

It is impossible to image the horrific moments the men on board must have experienced on the afternoon of April 7, 1945. At 1227 hrs, the attack began. At 1422 hrs, after two hours of the most violent hell imaginable, Yamato slipped beneath the waves. The mightiest steel deck ever made was covered with thousands of young men, rained on by armor-piercing bombs, machine gun fire and air-borne torpedoes. It must have been pure hell on earth, at sea.

What P.H. and I saw on the bottom, however, were not Allied armaments, but only the munitions of Yamato's own men — strewn like symbolic brass flowers on their dying ground. On land, we clear such remnants of war away and forget as best we can. But beneath the sea, they slowly dissolve into the sand over time, bearing witness to our past human stupidities.

Shaken to the darkest caverns of our minds by this unworldly landscape, we headed off in the dark for the ship herself, Yamato.