Soon we had left the houses and were among the cultivated lands, all of which Dramana informed us were worked by the Heuheua slaves. These laboured here in gangs for a year at a time, and then were returned to their women in the forests on the mainland, for, except as servants, none of them were allowed upon the island. Those lands were extraordinarily fertile, as was shewn by the crops on them, which, although much beaten down by the torrential rain, were now ready for harvest. They were enclosed by a kind of sea wall built of blocks of lava and must at some time have been reclaimed from the muddy shallows of the lake, which accounted for their richness. Everywhere about them ran irrigation channels that were used in the dry sowing season and controlled by the sluice gate that has been mentioned. That is all I have to say about the gardens, except that the existence of this irrigation system is to my mind another proof that these Walloos sprang originally from some highly civilized race. Their fields extended to that extremity of the island which was nearest to the Walloo coast, and I know not how far in the other direction, for I did not go there.
Standing upon this point we saw in the distance a number of moving specks upon the water. I asked Dramana if they were hippopotami, and she answered:
"No, Lord, they are the Hairy Folk who, in obedience to the summons of the god, cross the lake upon bundles of reeds that they may be ready to fight in the coming war against the Walloo. Already there are hundreds of them gathered upon the farther side of the mountain, and by to–night all their able–bodied men will have come, leaving only the females, the aged, and the children hidden away in the depths of the forests. On the third day from now they will paddle back across the lake, led by the priests under the command of Dacha, and attack Walloo."
"A great deal may happen in three days," I said, and dropped the subject.
We walked back towards the village and the cave mouth by the sea wall, upon the top of which ran a path, and thus at last came to the Rock of Offering, upon each side of which burned the two curious columns of flame that, I took it, were fed with natural gas generated in the womb of the volcano. They were not very large fires—at any rate, when I saw them—the flame may have been about eight or ten feet high, no more. But there they burned, and had done so, Dramana said, from the beginning of things. Between them, at a little distance, stood a post of stone with rings also of stone, to which the bride was bound. I noted that from these rings hung new ropes placed there to serve as the bonds of Sabeela during the coming night.
Having seen all there was to see on this Rock of Offering, including the steps by which the victim was landed, we went on to a long shed with a steep reed roof, which contained the machinery, if so I can call it, that regulated the irrigation sluice. It had a heavy wooden door which Dramana unlocked with an odd–shaped stone key that she produced from a bag she was wearing. This key, she told us, had been given to her by Dacha with strict orders that she was to return it after we had examined the place, should we wish to do so.
As it happened there was a good deal to examine. Near one end of the shed the main irrigation canal, which may have been twelve feet wide, passed beneath it. Here, under the centre of the roof, was a pit of which the water that stood in it prevented us from seeing the depth. On either side of this pit were perpendicular grooves cut in the solid rock, very deep grooves that were exactly filled by a huge slab of dressed stone six or seven inches thick. When this stone, or the upper part of it, was lifted out of the rock floor of the channel, where normally it stood in its niche, forming part of the bed of the channel, it entirely cut off the inflow of water from the lake, and was, moreover, tall enough to stop any possible additional inflow at a time of flood.
Perhaps I can make the thing clear in this way. When Good and I were last in London together we went to Madame Tussaud's and saw the famous guillotine that was used in the French Revolution. The knife of that guillotine, you will remember, was raised between uprights, and when brought into action, let fall again to the bottom of the apparatus, severing the neck of the victim in its course. Now imagine that those uprights were the rock walls of the pit, and that the knife, instead of being but a narrow thing, were a great sheet of steel, or rather stone. Then, when it was drawn to the top of the uprights from the niche at the bottom, it would entirely fill the space to the head of the grooves, and none of the water that normally passed over it could flow between the uprights, or rather walls, because the sheet of stone barred its passage. Now do you understand?
As Good, who was stupid about such matters, looked doubtful, Allan went on:
"Perhaps a better illustration would be that of a portcullis; even you, Good, have seen a portcullis, which, by the way, must mean a door in a groove. Imagine a subterranean or rather subaqueous, portcullis that, when it was desired to shut it, rose in its grooves from below instead of falling from above, and you will have an exact idea of the water door of the priests of Heu–Heu. I'd draw it for you if it wasn't so late."
"I see now," said Good, "and I suppose they wound the thing up with a windlass."
"Why not say with a donkey engine at once, Good? Windlasses had not occurred to the Walloos. No, they acted on a simpler and more ancient plan. They lifted it with a lever. Near the top of this slab of rock, or water door, was drilled a hole. Through this hole passed a bolt of stone, of which the ends went into the cut–out base of the lever, thus forming a kind of hinge. The lever itself was a bar of stone— evidently they would not trust to wood which rots—massive and about twenty feet long, so as to obtain the best possible purchase. When the door was quite down in its niche at the bottom of the bed of the channel, the end of the lever naturally rose high into the air, almost to the top of the pitched roof of the shed, indeed."
When it was desired to raise the door so as to regulate the amount of water passing into the irrigation channel beyond, or to cut if off altogether in case of flood, the lever was pulled down by ropes that were tied to its end by the strength of a number of men and that end was passed into, or rather under, one or other of half a dozen hooks of stone hollowed into a face of solid rock. Here, of course, it remained immovable until it was released, again by the united strength of a number of men, and flew back to the roof, letting the portcullis slab drop into its bed or groove at the bottom of the channel, thus admitting the lake water.
On the present occasion, as a great flood was anticipated, this slab was raised to its full extent, and when I saw it, the top of it stood five or six feet above the level of the water, while the end of the handle of the lever was made fast beneath the lowest hook of rock within a foot of the floor.
Hans and I examined this primitive but effective apparatus for preventing inundations very carefully. Supposing, thought I, that any one wanted to release that lever so that the door fell and water rushed in over it, how could it be done? Answer: it could only be done by the application of the united force of a great number of men pressing on the end of the lever till it was pushed clear of the point of the hook, when naturally it would fly upwards and the door would fall. Or, secondly, by breaking the lever in two, when, of course, the same thing would happen. Now two men, that is Hans and myself, could not possibly release this beam of stone from its hook; indeed, I doubt whether ten men could have done it. Nor could two men possibly break that beam of stone. Perhaps, if they had suitable marble saws, such as workers in stone use, and plenty of time, they might cut it in two, although it seemed to be made of a kind of rock that was as hard as iron. But we had no saw. Therefore, so far as we were concerned the task was impossible; that idea must be dismissed.