As the purpose of the principal hall is unusual, so also the chambers behind differ considerably from the usual arrangement, but they show some similarity to the inner chambers near the great hall of the central court. They are three lofty chambers or courts each provided with a side-chamber on the south side, which can also be entered from the open passage behind the wall of the Citadel. The side courts are connected with the throne-room by an intermediate chamber, and with the side corridors by another apartment, while they communicate with each other through the central court 35. In each of the two chambers that abut on the rear wall of the throne-room there is a circular walled well, and each of these chambers is completely walled in from the floor down to water-level with broken brick, asphalt, and mud. The wells in each case lie in the south-west corner of the chamber. The object of this solid walling-off of the wells must have been to secure absolutely pure water for the use of the royal household. The river water would naturally be well filtered by the earth through which it passed before reaching the wells. A peculiarity of this country at the present time is the fine distinction made between the various kinds of drinking water, as a natural result of the climate. The people distinguish the various kinds of water, such as sweet, salt, flat or brackish, much as we distinguish our alcoholic drinks, and as we speak of light or heavy beer, so the Oriental speaks of light or heavy water. The water of the Euphrates is famed, and is considered lighter than the water of the Tigris. One of the earlier governors of Bagdad drank Euphrates water exclusively, and had it sent daily from Musseyib. Another travelled from Bagdad to Constantinople with a large supply of Euphrates water stored in leather bottles, just as a celebrated modern traveller drank nothing but champagne during a long journey to Haïl in Central Arabia. Nowadays the water in most of the wells on the town site of Babylon, as in many other ruined sites, is brackish or salt and not good. I still do not understand fully why this should be the case; it certainly was not so in early times, otherwise it would be difficult to explain the number of wells found in all the ruins, where the soil is now so salt that the Arabs in early summer collect the upper crust of earth and from it obtain salt for cooking and saltpetre for gunpowder. As a result of this the ruins are extremely bare of vegetation, and stand out grey and barren in contrast with the surrounding plain, which is green, at any rate during the spring-tide, when there is some slight rainfall.