Babylonia is a remarkably productive country. The annual inundation of the rivers has covered its once rocky bottom with deposits of rich silt. Crops planted in such a soil, under the influence of a blazing sun, ripen with great rapidity and yield abundant harvests. "Of all the countries that we know," says an old Greek traveler, "there is no other so fruitful in grain." [5] Wheat and barley were perhaps first domesticated in this part of the world. [6] Wheat still grows wild there. Though Babylonia possessed no forests, it had the date palm, which needed scarcely any cultivation. If the alluvial soil yielded little stone, clay, on the other hand, was everywhere. Molded into brick and afterwards dried in the sun, the clay became _adobe_, the cheapest building material imaginable. BABYLONIA AN EARLY CENTER OF CIVILIZATION In Babylonia Nature seems to have done her utmost to make it easy for People to gain a living. We can understand, therefore, why from prehistoric times men have been attracted to this region, and why it is here that we must look for one of the earliest seats of civilization. [7] LOWER AND UPPER EGYPT Egypt may be described as the valley of the Nile. Rising in the Nyanza lakes of central Africa, that mighty stream, before entering Egypt, receives the waters of the Blue Nile near the modern town of Khartum. From this point the course of the river is broken by a series of five rocky rapids, misnamed cataracts, which can be shot by boats. The cataracts cease near the island of Philae, and Upper Egypt begins. This is a strip of fertile territory, about five hundred miles in length but averaging only eight miles in width. Not far from modern Cairo the hills inclosing the valley fall away, the Nile divides into numerous branches, and Lower Egypt, or the Delta, begins. The sluggish stream passes through a region of mingled swamp and plain, and at length by three principal mouths empties its waters into the Mediterranean. [Illustration: PHILAE The island was originally only a heap of granite bowlders. Retaining walls were built around it, and the space within when filled with rich Nile mud, became beautiful with groves of palms and mimosas. As the result of the construction of the Assuan dam, Philae and its exquisite temples are now submerged during the winter months, when the reservoir is full.] EGYPT THE GIFT OF THE NILE Egypt owes her existence to the Nile. All Lower Egypt is a creation of the river by the gradual accumulation of sediment at its mouths. Upper Egypt has been dug out of the desert sand and underlying rock by a process of erosion centuries long. Once the Nile filled all the space between the hills that line its sides. Now it flows through a thick layer of alluvial mud deposited by the yearly inundation. ANNUAL INUNDATION OF THE NILE