en, rather heavily loaded, they
started anew, always going northward through a sad and rough land. Now
they entered another bare and sterile region of vast extent, walking for
five days, without seeing a single trace of surface water. Had it not
been for their capacious water bottles they would have perished, and,
even with their aid, it was only by the strictest economy that they
lived. The evaporation from the heat was so great that after a mouthful
or two of water they were invariably as thirsty as ever, inside of five
minutes.

They passed from this desert into a wide, dry valley between bare
mountains, and entered a great cactus forest, one of the most wonderful
things that either of them had ever seen. The ground was almost level,
but it was hard and baked. Apparently no more rain fell here than in the
genuine desert of shifting sand, and there was not a drop of surface
water. Ned, when he first saw the mass of green, took it for a forest of
trees, such as one sees in the North, but so great was his interest that
he was not disappointed, when he saw that it was the giant cactus.

The strange forest extended many miles. The stems of the cactus rose to
a height of sixty feet or more, with a diameter often reaching two feet.
Sometimes the stems had no branches, but, in case they did, the branches
grew out at right angles from the main stem, and then curving abruptly
upward continued their growth parallel to the parent stock.

The stems of these huge plants were divided into eighteen or twenty
ribs, within which at intervals of an inch or so were buds, with
cushions, yellow and thick, from which grew six or seven large, and many
smaller spines.

Most of the cactus trees were gorgeous with flowers, ranging from a deep
rich crimson through rose and pink to a creamy white.

The green of the plants and the delicate colors of the flowers were
wonderfully soothing to the two who had come from the bare and burning
desert. There their eyes had ached with the heat and glare. They had
longed for shade as men had longed of old for the shadow of a rock in a
weary land. In truth they found little shade in the cactus forest, but
the green produced the illusion of it. They expected to find flowing or
standing water, but they went on for many miles and the soil remained
hard and baked, as it can bake only in the rainless regions of high
plateaus.

They found the forest to be fully thirty miles in length and several
miles in wi