At last there arrived on the hill-top a man who made up his mind he would ride through this valley! And so he did! Everybody said he was going to his death, but he was resolved to solve the mystery of the valley. He rode into it, and through it, and back again, and came out alive and well! Nevertheless he found the skeletons of wild animals, and of birds strewn the whole length of the valley.
It was a mystery, but it was all cleared up afterwards. The valley was fatal to all animals except man. But the Upas tree had nothing to do with it. The valley was filled with carbonic acid gas to the height of a couple of feet from the ground.
I cannot explain to you in this place how this gas is formed by plants. It would be a good plan for you to study up this subject, for it is quite curious, and very interesting. The gas is fatal to animal life. Neither man, beast, or bird can breathe it for even a short time and live. But the gas is heavier than the common air, and sinks in it. In this valley, as I have said, it extended only about two feet above the ground, and a man’s lungs were above it, so he could not inhale it. On horseback of course he was far above it. But low animals, and birds that alighted on the ground at once fell victims to it.
This led to an examination of the Upas tree stories, and most of them were found to be fables. Grass and flowers do grow around these trees in most places; birds sport upon their branches, and lizards run up and down unhurt; and it is possible to remain under them without injury of any kind.
But it is true that the juice of the upas is a powerful poison. The savages use it as a weapon to kill their enemies in war, and to slay the wild beasts. They dip the points of their spears and arrows in the poisonous sap. An animal dies in five or six minutes after being struck with one of these poisoned weapons. They take great precautions in collecting the sap, so terrible is their fear of this tree.
On some plants the blossoms are so small they can scarcely be seen by the naked eye, and on others they are of enormous proportions.
An African flower, the Aristolochia, has a large and curiously shaped blossom. It is shaped like a helmet with flaring edges, and the opening is so large that it will admit the head of a man, and can be worn as a hat.
The flowers of the Victoria Regia, which are shaped very much like those of our water lily, are a yard in circumference.
But the giant of blossoms is the Rafflesia Arnoldi. This is a long name, but the flower can bear it very well.
