Thus the plan of an excursion to the outlet of the Victoria N'yanza and the visit to Ripon Falls was completed in a few minutes. Speke had great difficulty in getting there at all; Long was obliged to ask many times before he received permission to go there, and then he had to fight his way down the river; and Stanley only succeeded in reaching the falls by accompanying the king on a warlike expedition against one of his rebellious tribes. The "Running" or "Flowing N'yanza" is the name given to a river; while "n'yanza," without any prefix, simply means water, and may apply to any body of that liquid, from the contents of a drinking-cup up to one of the great lakes, or even the ocean. This general use of the word was sometimes confusing, but by degrees our friends came to understand it; and as for the Running N'yanza, there could be no mistake about that. [Illustration: TREES AND CLIMBING PLANTS IN CENTRAL AFRICA.] Before they left the royal presence the king hinted that if the white men had anything for seeing in the dark he would like to have it produced. At Frank's suggestion, an appointment was asked for the evening of the second day from that date, as it would be necessary to unpack some of the cases and make arrangements which could not be hurried. The king gave the desired appointment, and the strangers went to their zeriba. Fred was puzzled to know what Frank intended to do, and as soon as they were out of hearing of the king he asked his cousin what he meant by hinting that they could enable his majesty to see in the dark. "Perhaps we cannot literally make him see in the dark," Frank responded, "but we can go quite the distance in that direction. We'll show him something he has never seen yet." "What is that?" "Gas." "Where'll you get it?" Fred inquired. "Make it ourselves," was the reply. "We haven't the New York Gas-Works at hand, but we'll get up a substitute." Fred made no reply, as he was well aware Frank had made his plans, or he would not be so confident. Frank continued that he would explain his process as soon as they reached the zeriba. He added that he should want Fred to help him, and the latter immediately promised to do everything he could to make the experiment successful. "You know," said Frank, as soon as they were seated in their zeriba, "how gas is made for illuminating purposes?" "Certainly I do," was the reply, "for I learned that when I studied chemistry." "Just run over the process," Frank suggested. "Let me see," responded his cousin. "The coal is baked in retorts, which are generally made of clay. They are closed up tight as soon as the coal is put in, and the hot fire beneath them causes the coal to give out its gas, which is carried away by iron pipes." "All right so far," said Frank. [Illustration: CHARGING A RETORT IN A GAS FACTORY.]