"The lake-dwellers of Asia and Africa are modern," said Doctor Bronson, "but those of Europe disappeared ages and ages ago. All the lakes of Switzerland once contained villages built on piles, and some of them were quite extensive. From twenty to fifty villages have been explored in each of the larger Swiss lakes, and many others in the smaller ones. Most of them date from the age of stone implements, before the discovery of metals, and in the remains of the villages many weapons and utensils of stone are found. One village covered an area of three acres, and stood on piles or posts of 'hard wood'--beech, oak, and fir--and most of them ten or twelve feet long. There were about one hundred thousand of these piles. The village was in the middle of a small lake, and had a bridge, connecting it with the shore. There are two sets of piles, one above the other, so that it is evident the village was occupied at two different periods. "Another lake was completely surrounded by these dwellings, and among the relics discovered there are articles of wood, horn, bone, bronze, and gold. When you visit Switzerland you will see, at Lucerne, Zurich, and other places, some of the relics brought up from the lakes, and putting us face to face, as it were, with the people of a prehistoric age." CHAPTER XVIII. DR. LIVINGSTONE AND HIS DISCOVERIES. When the work of "wooding up" was completed the steamer continued her voyage. An effort was made to visit the western shore; but at every halting-place the natives came down in considerable numbers, and their movements were so threatening that Doctor Bronson did not consider it judicious to attempt to land. As he was under obligation to the Egyptian authorities for the use of the steamboat he did not wish to do anything, however slight, that might lead to hostilities. For this reason he declined to go on shore where there was the slightest possibility of trouble with the natives, and contented himself with looking at it from the deck of the steamer. While they were sitting under the sheltering awning and studying the landscape before them Fred asked about the travels and explorations of Dr. Livingstone. [Illustration: LIVINGSTONE'S HOUSE AT ZANZIBAR.] "He was the son of a poor weaver in Glasgow," was the reply, "and gained the most of his early education at an evening school while working in a cotton-mill. Afterward he managed to devote his winters to study, and supported himself by working for the rest of the year. He was born March 19, 1813, and died May 1, 1873. [Illustration: DAVID LIVINGSTONE.]